Electrical & Control Systems Procedures

This page lists 83 maintenance procedures for electrical & control systems, drawn from HIT Srl's internal procedure library extracted from manufacturer service manuals.

HIT Srl supplies electrical and control-system spare parts for this class of machine.

General guidance only — always follow the operation and maintenance manual for your specific machine.

Lighting

• What is the correct sequence to replace a pole-mounted rotating beacon?

  1. Put the machine in service position.
  2. Undo the wing nut which fixes the rotating beacon to the pole.
  3. Lift the rotating warning beacon off.
  4. Install the new rotating beacon.
  5. Tighten the wing nut.

• What is the correct sequence to replace a roof-mounted rotating beacon?

  1. Put the machine in service position.
  2. Turn the lamp dome counter-clockwise.
  3. Remove the screws securing the lamp base.
  4. Unplug the connector.
  5. Replace the beacon.
  6. Fit in reverse order.

• What is the correct sequence to replace the front headlight (low/high beam) bulb?

  1. Unscrew the fastening screws and pull out the headlight unit.
  2. Unscrew the cover.
  3. Remove the bulb holder's retaining clips and pull the assembly out of the headlight unit.
  4. Remove the connector plug.
  5. Replace the halogen bulb.
  6. Reinsert the connector plug.
  7. Reinsert the assembly into the headlight unit and refit the bulb holder's retaining clip.
  8. Refit the cover, screwing it back on.
  9. Refit the headlight unit and re-tighten the fastening screws.

  Note: Avoid direct contact with hands when fitting a halogen bulb, since this impairs its performance.

• What is the correct sequence to replace the front position light and front direction indicator bulbs?

  1. Unscrew the fastening screws and remove the lens.
  2. Replace the position light's spherical bulb.
  3. Replace the front direction indicator's spherical bulb.
  4. Refit the lens and re-tighten the fastening screws.

  Note: Do not overtighten the lens fastening screws, to avoid breaking it.

• What is the correct sequence to replace the side direction indicator bulb?

  1. Unscrew the lens fastening screws and remove it.
  2. Replace the spherical bulb.
  3. Refit the lens and re-tighten the fastening screws.

  Note: Do not overtighten the lens fastening screws, to avoid breaking it.

• What is the correct sequence to aim the front headlights after a full dismount?

  This operation should be carried out by qualified personnel with appropriate equipment; contact an authorised workshop. An approximately correct aiming can still be obtained as follows.

  1. Park the machine, with tyres at the prescribed pressure, on level ground facing a light-coloured wall.
  2. Mark two crosses on the wall corresponding to the centres of the two headlights.
  3. Move the machine back 10 metres and switch on the low beams; the distance between the crosses and the reference points should equal 10% of the height between the crosses' centre and the ground.
  4. Adjust the beam using the headlight's adjustment screws if needed.

• What is the correct sequence to replace the rear LED light's bulbs?

  If the lights driven by the LED driver board fail, the complete light unit must be replaced.

  1. Unscrew the lens fastening screws and remove it.
  2. Replace whichever bulb(s) need it, if present.
  3. Refit the lens and re-tighten the fastening screws.

• What is the correct sequence to replace the reversing light bulb?

  1. Remove the lens's rubber protector.
  2. Unscrew the lens fastening screw and lower it.
  3. Replace the halogen bulb.
  4. Reposition the lens, re-tighten the fastening screw, and refit the rubber protector.

• What is the correct sequence to replace the rear side direction indicator bulb?

  1. Unscrew the lens fastening screws and remove it.
  2. Replace the spherical bulb.
  3. Refit the lens and re-tighten the fastening screws.

  Note: Do not overtighten the lens fastening screws, to avoid breaking it.

• What is the correct sequence to replace the 20'-40' work light bulb?

  1. Remove the lens by inserting a screwdriver between the edge of the rubber protector and the lens itself, then levering it out.
  2. Replace the bulb.
  3. Refit the lens into the rubber protector.

  Note: Do not force the lens excessively with the screwdriver while levering it out, to avoid breaking it.

• What is the correct sequence to replace the left cargo body light bulb?

  1. Remove the lens by inserting a screwdriver between the edge of the rubber protector and the lens, then levering it out.
  2. Replace the bulb.
  3. Refit the lens into the rubber protector.

  Note: Do not force the lens excessively with the screwdriver while levering it out, to avoid breaking it.

• What is the correct sequence to replace the right cargo body light bulb?

  1. Remove the lens by inserting a screwdriver (or similar tool) between the edge of the plastic protector and the lens, then levering it out.
  2. Replace the bayonet-type bulb.
  3. Refit the lens into the plastic protector, pressing it into place.

  Note: Do not force the lens excessively with the screwdriver while levering it out, to avoid breaking it.

• What is the correct sequence to replace the auxiliary work light bulb?

  1. Remove the lens by inserting a screwdriver between the edge of the rubber protector and the lens, then levering it out.
  2. Replace the halogen bulb.
  3. Refit the lens into the rubber protector.

  Notes:

  • Do not force the lens excessively with the screwdriver while levering it out, to avoid breaking it.
  • Avoid direct contact with hands when fitting a halogen bulb, since this impairs its performance.

• What is the correct sequence to remove a light fixture (headlights, strobe light, or working lights) for lamp replacement?

  Applies to the front headlights, rear headlights, boom strobe light, boom working lights, boom operation lights, and chassis working light, each at its own mounting point.

  1. Remove the bolts and cover at the fixture's mounting point.
  2. Replace the lamp if necessary.

• What lighting-circuit and bypass-switch operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the condition and rating of the fuses.
  2. Check the light-switch stalk's operation.
  3. Check the direction indicators and hazard lights' operation.
  4. Check the front/rear/stop lights' operation.
  5. Check the boom lights' operation.
  6. Check the reversing lights' operation.
  7. Check the rotating beacon's operation.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

Batteries

• What is the correct sequence to check the start battery?

  1. Check the battery voltage from the operating menu for the electrical system: with the engine off it should be 23-25 V, and with the engine at max speed (2000 rpm) it should be 27-29 V.
  2. Turn off the engine and the main electric power.
  3. Check that the battery terminals are free from dirt, greasing them with terminal grease if needed.
  4. Check the fluid level in the battery cells, topping up with distilled battery water if needed (the electrolyte level should be 10 mm above the cells).

  Note: Battery electrolyte contains corrosive sulphuric acid; remove any electrolyte from skin immediately and wash with soap and plenty of water, and if it splashes into the eyes, rinse immediately with plenty of water and seek immediate medical attention.

• What is the correct sequence to check the electrolyte level of the batteries?

  The starting batteries are of the maintenance-free type, so it should not be necessary to top up with electrolyte during their life, but the level should preferably be checked once or twice a year.

  1. Check the electrolyte level, which should be about 10 mm above the cells.
  2. Top up with de-ionized water as necessary.

• What is the correct sequence to start the machine from another battery?

  1. Make sure the auxiliary batteries are connected in series, so that the correct system voltage will be supplied.
  2. Connect the red (+) jumper cable to the auxiliary battery.
  3. Connect the other end of the red (+) jumper cable to the machine's battery.
  4. Connect the black (-) jumper cable to the auxiliary battery.
  5. Connect the other end of the black (-) jumper cable to a location some distance away from the machine's battery, such as the negative cable connection on the chassis.
  6. Start the engine.
  7. Disconnect the jumper cables in exactly the reverse order.

  Notes:

  • Batteries emit oxyhydrogen, an explosive gas; a spark, for example from incorrectly connected starting cables, could cause a battery to explode and result in serious injury and damage.
  • Do not disturb the jumper cables while starting, as sparks may otherwise be caused, and do not lean over either battery.
  • Do not disconnect the machine's own battery cables.

• What is the correct sequence to check the start battery?

  1. Check the battery voltage from the operating menu for the electrical system: with the engine off it should be 23-25 V, and with the engine at max speed (2000 rpm) it should be 27-29 V.
  2. Turn off the engine and turn off the system voltage.
  3. Check that the batteries are clean on top, to prevent leakage currents between cells that reduce capacity, wiping clean with a cloth and clean warm water without detergent.
  4. Check that the battery terminals are free from dirt, lubricating them with terminal grease if needed.
  5. Check the fluid level in the battery cells, topping up with distilled battery water if needed (the electrolyte level should be 10 mm above the cells).

  Note: Battery electrolyte contains corrosive sulphuric acid; use protective safety goggles and gloves, remove any electrolyte from skin immediately and wash with soap and plenty of water, and if it splashes into the eyes, rinse immediately with plenty of water and contact a doctor immediately.

• What battery cables must be checked for correct clamping, rubbing risk and damage on a diesel-powered machine?

  1. Check the plus cable between the battery and the battery disconnector.
  2. Check the plus cable between the battery disconnector and the starter motor.
  3. Check the plus cable between the starter motor and the alternator.
  4. Check the plus cable between the battery disconnector and the main fuses.
  5. Check the plus cable between the starter motor and the preheating relay.
  6. Check the plus cable between the preheating relay and the preheating coil.
  7. Check the ground cable between the battery and the frame.
  8. Check the ground cable between the engine and the frame.

  Note: Incorrectly clamped or damaged battery cables are a fire hazard and personal injury risk; repair or replace damaged clamps and change any battery cable showing signs of damage.

• What is the correct sequence to clean and check unsealed batteries?

  1. Thoroughly clean the batteries, cables and compartment, removing carbon oxide and dirt that can cause voltage drops.
  2. Check through the plugs that the electrolyte level in each cell is about 10-12 mm above the top edge of the plate.
  3. If necessary, top up using only distilled water, with the batteries cold and settled, through the filler holes.

  Notes:

  • Do not smoke while checking the battery fluid level; the battery produces flammable gas.
  • The electrolyte is an acid solution hazardous to skin and eyes.
  • When checking battery charge, use a voltmeter or hydrometer, and never place any metal object between the terminals, since sparks can cause an explosion.
  • If the electrolyte is frozen, the battery may explode if you attempt to charge it or start the engine; keep the battery charged to prevent the electrolyte from freezing.

• What is the correct sequence to jump-start the engine using another machine's battery?

  1. Make sure the two machines do not touch each other.
  2. Make sure both ignitions are off with the key removed.
  3. Connect one end of the positive auxiliary cable to the positive terminal of the discharged battery.
  4. Connect the other end of the positive auxiliary cable to the positive terminal of the charged battery.
  5. Connect the negative auxiliary cable to the negative terminal of the charged battery.
  6. Connect the other end of the negative auxiliary cable to the engine block of the assisted machine, away from its battery.
  7. Start the assisted machine's engine, without holding the starter engaged for more than 5 seconds.
  8. Disconnect the cables in reverse order, starting with the negative cable from the engine block.

  Note: Do not hold the starter engaged for more than 5 seconds.

• What is the correct sequence to maintain the batteries in serviceable condition?

  1. Check the electrolyte level regularly, adding distilled water if necessary to bring it to 3/8 inch above the separator plates, without overfilling.
  2. Keep the tops of the batteries, terminals and cable clamps clean, washing them when necessary with a baking soda and water solution and rinsing with clear water.
  3. Inspect the cables, clamps and hold-down brackets regularly, replacing any damaged parts and re-applying a light coating of grease to the terminals and cable clamps when necessary.
  4. Check the electrical system if the batteries become discharged repeatedly, using the charging circuit conditions (fully charged/low battery combined with the observed charging rate) as an indication of which component may be faulty.

  Notes:

  • Overfilling with water can cause poor performance or early battery failure.
  • Do not allow the baking soda and water cleaning solution to enter the battery cells.
  • A high charging rate on fully charged batteries will damage the batteries and other electrical components.

Diagnostics

• What is the correct sequence to access the diagnostics menus on the control system display?

  1. Navigate to the service menu using the arrow keys.
  2. Select the service menu using the function key.
  3. At the safety menu, enter the code to access the diagnosis menus (11111).
  4. Select diagnostics.
  5. Choose which control unit to investigate using the function keys and confirm (only control units actually present on the machine are shown); use the arrow keys to choose the next diagnosis menu within the selected control unit.

• What is the correct sequence to read out and respond to an error code?

  1. Stop the machine and identify the error code level and specific error code number.
  2. If the alarm level is Stop, stop the engine; if it is Warning or Information, the engine may keep running.
  3. Read off the error code and carry out the actions listed in the error code table for that code.

  Notes:

  • Stop alarms indicate a malfunction that may affect operator safety or cause a breakdown; stop work with the machine and contact service immediately.
  • Warning and information alarms indicate malfunctions that do not require stopping work immediately, though machine capacity may be limited; carry out the actions in the error code table as soon as possible.

• What is the correct general troubleshooting procedure?

  1. Check that battery voltage is available: the battery disconnect switch must be in position 1, battery voltage should be 22-30V, and fuses must be intact.
  2. Check that all oil and fluid levels are normal (fuel, engine oil, transmission oil, brake system oil, hydraulic oil, coolant, washer fluid).
  3. Check whether there are error codes.
  4. If there are error codes, use the error code lists as a guide for recommended actions.
  5. If there is no error code, or the problem remains, use the function description for the function in question to identify the components involved and the conditions required to activate the function.

• What is the correct sequence to troubleshoot a malfunction that has no associated error code?

  1. Choose the appropriate function group to find the function and sub-function that caused the symptom.
  2. Read the function description for the function in question to understand which components are affected and how they interact.
  3. Use the function description and check the signals for the function in question to find where in the function chain the signal or reaction is incorrect.
  4. Since the fault is probably between the two units where the signal fails, start by checking the component that should send the signal.
  5. If the sending component seems correct, check transmission of the signal (electric wiring or hydraulic hoses).
  6. If the leads or hoses between the components seem in order, check the component that receives the signal.

• What is the correct sequence to troubleshoot a malfunction using an error code?

  1. Read out the error code from the display.
  2. Look up the error code in the error code lists.
  3. Follow the instructions in the 'Action' field.
  4. Use diagnostic menus and circuit diagrams to determine whether the input signal to the control unit is correct.
  5. Use the function group for more information if needed, including work instructions for how components are checked, cleaned, or adjusted.
  6. If possible, eliminate the component as the fault source by testing it individually: electric components can sometimes be checked with resistance measurements using a multimeter; hydraulic components are often checked by measuring pressure, and valves can sometimes be activated mechanically to determine whether the malfunction is electric or hydraulic.
  7. If the component's measured values are correct, continue by troubleshooting the electric cabling and hydraulic hoses.
  8. If the cable is not defective, turn off the main electric power with the battery disconnector before reconnecting the lead to the control unit.
  9. Disconnect the cable harness from the component in question.
  10. Turn on the main electric power with the battery disconnector.
  11. Turn the ignition key to the operating position.
  12. Check that voltage reaches the component.

  Note: The main electric power must be turned off with the battery disconnector before disconnecting the cable harness from the component.

• What is the correct sequence to troubleshoot a suspected cable harness fault?

  1. Study the relevant circuit diagram, checking where the suspected cable is connected and, if applicable, where it is spliced.
  2. Turn off the main electric power with the battery disconnector.
  3. Unplug the connector at the control unit or component in question.
  4. Check for an open circuit: measure the resistance between the connections for the component in the connector at the control unit or component, and confirm the resistance corresponds to the component; otherwise there may be an open circuit or short circuit in the cable harness and/or component.
  5. Check for a short circuit to the frame: unplug the connector at both the control unit and the component, measure the resistance of one lead at a time between the lead and a frame-connected part of the machine, and confirm the multimeter shows endless resistance.

  Notes:

  • Perform troubleshooting for all cables in the same way to avoid damage to control units, components, or measuring equipment.
  • Some components cannot be checked without power supplied to them.

Battery

• What is the correct sequence to replace the battery disconnector?

  1. Put the machine in service position.
  2. Open the cover concealing the battery.
  3. Disconnect the negative cable and then the positive cable from the battery.
  4. Thread off the rubber protectors on the battery disconnector.
  5. Remove the two nuts and release the cables from the battery disconnector.
  6. Remove the two screws which hold the main battery disconnector in the bracket.
  7. Replace the battery disconnector.
  8. Fit in reverse order.

  Notes:

  • Never turn off the voltage with the battery disconnector while the engine is running, or the alternator may be damaged.
  • The battery disconnector cannot be used as an emergency stop.
  • Keep the positive and negative cables apart to avoid short-circuiting.

• What is the correct sequence to replace the starter batteries?

  1. Put the machine in service position.
  2. Disconnect the cables from the battery terminals, disconnecting the negative cable first.
  3. Replace the batteries.
  4. Connect the cables to the battery terminals, connecting the negative cable last.

  Notes:

  • Battery electrolyte contains corrosive sulphuric acid; remove electrolyte from skin immediately with soap and water, and seek medical attention if it splashes into the eyes.
  • Hydrogen gas forms at the batteries and can be ignited by welding sparks, causing a powerful explosion; disconnect the battery with the battery disconnector before welding.
  • Never connect the battery terminals to each other or to ground, as this short-circuits the battery with risk of explosion, fire, or personal injury.
  • Exercise care when reconnecting the cables to avoid a short circuit.

• What is the correct sequence to replace the auxiliary start connector?

  1. Put the machine in service position.
  2. Disconnect the cables from the battery terminals, disconnecting the negative cable first.
  3. Undo the two cables, undo the four fixing screws, and remove the auxiliary start connector.
  4. Fit in reverse order.

  Note: Exercise care when reconnecting the cables to avoid a short circuit.

• What is the correct sequence to start the engine using booster batteries or a starting generator?

  1. Make sure the parking brake is applied and all electrical controls are off.
  2. Connect one jumper cable to the positive terminal of the booster battery, and the opposite end of the same cable to the positive terminal of the machine's battery.
  3. Connect the other cable to the negative terminal of the booster battery, and the opposite end to a good ground connection on the machine's frame, away from the battery.
  4. Start the engine in the normal manner.
  5. After the engine has started, first disconnect the negative booster cable from the frame, then remove the positive booster cable.

  Notes:

  • Booster batteries should only be connected by personnel trained in their proper use; connecting them incorrectly can cause severe injury or equipment damage.
  • Battery electrolyte contains sulfuric acid; avoid contact with skin, eyes or clothing, flush with water for at least 15 minutes if it contacts eyes, drink large quantities of water (do not induce vomiting) if swallowed, and call a physician immediately.
  • Batteries produce explosive gases when charging or discharging; always wear eye protection when using booster batteries or starting generators.
  • Do not try to start the engine by towing or pushing.

• What checks and maintenance should be performed on the batteries?

  1. Check that the batteries are correctly fastened, clean, and dry; if humidity is found, identify and eliminate the cause.
  2. Check the battery charge condition through the special spy cap.
  3. Check the electrolyte level in each cell by loosening the covers and making sure the elements are covered with liquid; top up with distilled water if the level is too low.
  4. Clean and properly tighten the battery terminals, protecting the connections with vaseline.

  Notes:

  • Disengage the battery disconnecting switch before starting work.
  • Do not rest objects or tools on the batteries, due to short-circuit danger.
  • Do not smoke or use flames while checking the battery electrolyte, since acid vapours are flammable.
  • Electrolyte is dangerous for skin and eyes; wear protective clothing (gloves, eyewear, helmet) during inspection and maintenance.

• What battery and start-circuit operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the battery charge.
  2. Check the condition of the battery cables.
  3. Check the battery fluid level.
  4. Clean the battery terminals and connections.
  5. Apply protective grease to the battery terminals and connections.
  6. Check the start anti-repeat device's operation.
  7. Check the battery disconnector's operation.
  8. Check the anti-repeat device's wiring.
  9. Check the declutch device's operation.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

• Setting up a focus I infrakey receiver on a crane radio control system

  1. Connect the focus I infrakey receiver to the radio receiver.
  2. Insert a charged battery into the battery compartment of the transmitter.
  3. Release the STOP pushbutton on the transmitter if locked, and turn on the transmitter.
  4. Press the set-up pushbutton on the focus I infrakey receiver until its LED blinks, then release the button.
  5. Press the (Crane) On pushbutton on the transmitter until the LED on the focus I infrakey receiver blinks rapidly; release the pushbutton and the LED will go off.
  6. Affix the INFRAKEY OK sticker above the set-up pushbutton. The focus I infrakey receiver can now recognize the transmitter's exclusive security telegram.

  Note: Follow these steps when replacing a focus I infrakey receiver, or upgrading an existing radio system with focus I.

Alternator

• What is the correct sequence to check the alternator's brushes?

  1. Thoroughly clean the slip rings.
  2. Check the wear and contact condition of the brushes.
  3. If necessary, replace the complete brush holder with one of the same type.

• What precautions must be observed when working on or around the alternator?

  1. Do not ground the output wires or field wires between the alternator and the regulator, and never run an alternator on an open circuit.
  2. Do not accidentally reverse the battery connections; if a booster battery is used, connect positive to positive and negative to a chassis ground.
  3. Never disconnect the batteries while the alternator is operating, since the resulting voltage spike will damage the diodes.

  Note: Grounding the alternator's output or field wires, or reversing battery polarity, will destroy the diodes.

• What is the correct sequence to adjust the alternator drive belt tension?

  The nominal deflection of the alternator drive belt is one centimetre under a pressure of 42 N (4.2 kg). A belt is considered used once it has run for 10 minutes or longer.

  1. Loosen the adjusting screw.
  2. Loosen the adjustment link locking capscrew.
  3. Loosen the pivot capscrew and nut.
  4. Use a belt tension gauge to measure belt tension.
  5. Turn the alternator adjusting screw clockwise to tighten the belt to the correct tension.
  6. Tighten the adjusting screw locknut against the retainer.
  7. Tighten the adjustment link locking capscrew to the specified torque (80 Nm).
  8. Tighten the pivot capscrew and nut to the specified torque (47 Nm).

• What is the correct sequence to remove the alternator drive belt?

  1. Loosen the adjusting screw locknut.
  2. Loosen the adjustment link locking capscrew.
  3. Loosen the alternator mounting capscrew.
  4. Turn the adjusting screw counterclockwise to release tension.
  5. Remove the alternator belt.

• What is the correct sequence to install the alternator drive belt?

  1. Install a new belt on the alternator pulley.
  2. Turn the adjusting screw clockwise to increase belt tension, or counterclockwise to decrease it, following the belt tension adjustment procedure.

  Notes:

  • To prevent damage, do not roll or pry a belt over the pulley.
  • Too tight a drive belt is destructive to the bearings of the driven part, while a belt that is too loose will slip.

Power & charging

• What is the correct sequence to connect booster batteries or a starting generator to start the engine?

  Used if the machine's batteries are weak or discharged.

  1. Make sure the parking brake is applied and all electrical controls are OFF.
  2. Connect one jumper cable to the positive (+) terminal of the booster battery, and the opposite end to the positive (+) terminal of the battery on the machine.
  3. Connect the other cable to the negative (-) terminal of the booster battery, and the opposite end to a good ground connection on the machine's frame, away from the battery.
  4. Start the engine in the normal manner.
  5. After the engine has started, first disconnect the negative (-) booster cable from the frame, then remove the positive (+) booster cable.

  Notes:

  • Do not try to start the engine by towing or pushing.
  • Booster batteries should only be connected by personnel specifically trained in their proper use.
  • Batteries contain sulfuric acid which can cause severe burns; avoid contact with skin, eyes, or clothing.
  • Batteries produce explosive gasses when being charged or discharged; always wear eye protection when using booster batteries or starting generators.

• What safety precautions and checks apply to the machine's starting batteries?

  1. Before starting work, disengage the battery disconnecting switch.
  2. Sight check: make sure the batteries are correctly fastened, clean and dry.
  3. Battery charge check: view the condition of the charge through the special spy cap.
  4. Electrolyte level check: loosen the covers and make sure the elements are covered with liquid; if the level is too low, top up with distilled water.
  5. Cleaning: clean and tighten the battery terminals properly, and protect the connections with vaseline.

  Notes:

  • Do not rest objects or tools on the batteries (short-circuit hazard).
  • Do not smoke or use flames while checking the battery electrolyte, since the acid vapours are inflammable.
  • Electrolyte is dangerous for skin and eyes; always wear protective clothing (gloves, eyewear, helmet) during inspection and maintenance.

• What first aid should be given for caustic burns from battery acid or oil/diesel fuel?

  1. For skin causticisation from battery acid: remove the clothing, then wash with running water, taking care not to affect healthy parts.
  2. For eye causticisation from battery acid, lubricating oil or diesel fuel: wash the eye with water for at least 20 minutes, keeping the eyelids open so water runs over the eye's edge, moving the eye in all directions.

Fuses

• What is the correct sequence to check and replace the main fuses?

  1. Turn off the main electric power with the battery disconnector.
  2. Remove the plastic cover.
  3. Check and replace fuses as needed (rated at 25 A).
  4. Turn on the electric power again.

• What is the correct sequence to check and replace the circuit fuses?

  1. Turn off the main electric power with the battery disconnector.
  2. Remove the cover over the electrical distribution box in the cab.
  3. Remove the cover from the fuse holder.
  4. Check that the fuses are intact and replace as needed, referring to the fuse chart for each fuse.

• What is the correct sequence to change a fuse?

  1. Turn off the main electric power (battery disconnector).
  2. Remove the cover from the fuse holder.
  3. Check that fuses are intact and change any that are not.

  Note: Always use fuses with the correct ampere rating, to avoid risk of cable damage and fire in cable harnesses.

  Confirmed across independent manufacturers’ manuals.

Control Systems & can Bus

• How often should limit switches and electrical controls be functionally checked?

  Periodicity: efficiency check daily

  1. Efficiency check of limit switches and their indicators: performed daily by the operator; any problems must be immediately notified to maintenance personnel.
  2. Efficiency check of electrical controls (keyboard, joysticks, joystick switches) and their indicators: also performed daily by the operator.
  3. Fastening check: check the integrity and fastening of switches/controls and their connections, cleaning as necessary.

  Notes:

  • Before starting inspection, make sure no one can start the machine, unless expressly asked to do so.
  • Limit switches are safety devices; if not in good operating condition, this could be hazardous for people and the machine.

• What is the correct sequence to replace the transmission control unit (ECU793)?

  1. Put the machine in service position.
  2. Disconnect the connector(s) from the control unit.
  3. Unscrew the screws that hold the control unit and lift it away.
  4. Install the new control unit in reverse order.

  Note: Make sure the replacement control unit has the correct part number.

• Checking the generator mounting on a rubber tyred gantry crane

  1. Remove the protective net.
  2. Tighten the flex plate mounting screws to a tightening torque of 80 N.m.
  3. Tighten the generator mounting screws.
  4. Install the net back in place.
  5. Check the condition of the vibration dampers.

  Note: The electric systems must be serviced and repaired by trained personnel, due to the high voltage involved.

• Diagnosing a CAN bus communication fault on a mobile harbour crane's electronic control system

  1. Identify which unit, keyboard, joystick or encoder the alarm message names as not responding (for example 'Unit x is not responding', 'Cabin keyboard not responding', or 'Right/Left joystick not responding').
  2. Check that the named unit is connected correctly to its connector on the machinery room panel (or, for the keyboard or joystick, to its dedicated cable connector), and that it is powered.
  3. Check the integrity of its CAN cable.
  4. Check that the CAN line is correctly terminated: the resistance between the high and low lines must read 120 Ohm at both ends (one termination resistor sits on the truck panel, the other on the top cabin's panel, or via the keyboard/joystick jumper).
  5. For the cabin keyboard specifically, also check that the 4 switches on the light blue block behind the keyboard are all ON.
  6. If none of these checks finds the fault, the unit, keyboard, joystick or encoder itself may be damaged and must be changed.

  Note: Before following these checks, first exclude the possibility that crane movements or solenoid valve ignition are blocked by the programming logic itself (check all conditions required to activate the logic). Most malfunctions of this kind are electrical problems or sensor trouble, and can be solved using the wiring diagrams as a guide.

Wiring & connectors

• What is the correct sequence to replace the ignition switch?

  1. Put the machine in service position.
  2. Remove the steering wheel and steering panel covers.
  3. Unplug the connector from the ignition switch.
  4. Replace the ignition switch.
  5. Refit in the reverse order.

  Note: Torque the nut in the centre of the steering wheel to 40 Nm (±5 Nm).

• What general wiring and connections are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the condition of the electrical boxes and their components.
  2. Check the VHF radio wiring.
  3. Check the condition of electrical and electronic plugs and connections.
  4. Check the data radio terminal's wiring.
  5. Check the VHF radio and microphone's operation.
  6. Check the data radio terminal's operation.
  7. Check the machine's general wiring.
  8. Check the condition of plugs and connections.
  9. Check the condition of the junction boxes.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

Dashboard Switches

• What is the correct sequence to replace a dashboard switch?

  1. Put the machine in service position.
  2. Remove the screws securing the instrument panel and lift up the panel.
  3. Disconnect the pin terminal from the switch and any bulb socket.
  4. Remove the bulb socket using pliers.
  5. Replace the switch.
  6. Fit in reverse order.

• What is the correct sequence to replace a dashboard indicator lamp?

  1. Put the machine in service position.
  2. Remove the screws securing the instrument panel and lift up the panel.
  3. Disconnect the bulb socket pin terminal.
  4. Open the bulb holder using pliers.
  5. Replace the bulb.
  6. Fit in reverse order.

• Calibrating the load weighing system on a mobile harbour crane

  1. Select the gain corresponding to the load cells used, via the dip switches on the amplifier cards (on models with two loading cells, the amplifier cards must be the same type).
  2. Adjust the card trimmers so that, at no load, on the I/O test masks, the currents of the two inputs (or of the single input on smaller models) read between 17 and 19 mA and have identical values.
  3. Access the weight calibration mask and store the currents and the minimum weight.
  4. Hoist a certified load, set the weight, and store the currents detected in the weight calibration mask.
  5. Check that, with the weight raised, the current obtained at maximum load is at least 4 mA per cell; if the estimated current at maximum load is below 4 mA, the gain set is wrong and the procedure must be repeated from the gain selection step.

  Note: Perform this calibration with the boom and winch in an intermediate position and no weight attached.

Multi Function Lever

• What is the correct sequence to replace the multi-function lever?

  1. Put the machine in service position.
  2. Remove the steering wheel: remove the centre cover and unscrew the nut securing the steering wheel, then remove the steering wheel, tapping carefully with a mandrel the same diameter as the steering column if it is firmly fixed, while lifting the steering wheel at the same time; on an early model, if this does not loosen the steering wheel, fabricate and use a withdrawing tool — drill two holes in the steering wheel hub using a washer as a template, cut M6 threads in the holes, place the withdrawing tool over the steering wheel hub and fix it with two screws, then screw in the centre screw and tighten it until the steering wheel comes loose, and remove the steering wheel.
  3. Remove the lower steering panel cover (six screws).
  4. Remove the upper steering panel cover (two screws).
  5. Remove the Allen screws securing both levers.
  6. Remove the covers from the steering column (seven screws).
  7. Thread the lever through the lower cover.
  8. Remove the nine clips holding the instrument panel by pressing in the centre pin on each clip, then raise the instrument panel slightly.
  9. Cut the cable ties securing the cable harness.
  10. Unplug the connector for the multi-function lever in question.
  11. Withdraw the cables and multi-function lever.
  12. Replace the multi-function lever.
  13. Fit in reverse order.

  Notes:

  • Torque the socket cap screws that hold the multi-function lever to the steering column to 2.5-3.0 Nm.
  • Torque the nut in the centre of the steering wheel to 40 Nm (±5 Nm).
  • Reuse the instrument panel clips by re-inserting the centre pin and pressing it flush with the head on fitting.

• What joystick operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the joystick's wiring.
  2. Check the condition of the joystick.
  3. Check for oil leaks from the joystick's pipes, fittings and components.
  4. Check the joystick's electrical manoeuvre functions.
  5. Check the joystick's mechanical operation.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

• Programming minimum and maximum joystick function speeds with the tele-teach-in battery on a crane radio transmitter

  1. Switch off the transmitter.
  2. Insert a charged tele-teach-in battery into the battery compartment of the transmitter.
  3. Press the programming pushbuttons "+" and "-" on the tele-teach-in battery simultaneously and switch on the transmitter; keep them depressed until the transmitter's dual-colour LED starts flashing quickly green.
  4. When the green LED on the receiver illuminates, press the Start or (Crane) On pushbutton if equipped, then press both programming pushbuttons again to enter tele-teach-in operating mode.
  5. To set the minimum speed: push the joystick toward the desired function, not moving it beyond 50%, then adjust the minimum speed with the "+" and "-" pushbuttons by finding the point where the hydraulic valve begins to react.
  6. To set the maximum speed: push the joystick to its end position for the desired function, then adjust the maximum speed with the "+" and "-" pushbuttons by finding the point where the hydraulic valve reaches its maximum travel, without over-actuating the pushbuttons afterward.
  7. Repeat the minimum/maximum speed steps for each further joystick function.
  8. To finish, press both programming pushbuttons simultaneously, release them, and switch the transmitter off and on again to return to normal operating mode. On systems with a speed switch, all functions must be reprogrammed at each corresponding speed.

  Note: This function is relevant only for distributors who program equipment with manufacturer- or machine-specific unit data. Read the full instructions carefully before beginning. Only one function can be programmed at a time; if the crane movements are executed too fast or in a jerky manner and this is not being corrected by qualified programming, contact the distributor or the manufacturer instead.

Entertainment

• What is the correct sequence to replace the radio antenna?

  1. Put the machine in service position.
  2. Undo the screws which fix the roof panel and remove the roof panel.
  3. Undo the antenna cable connector.
  4. Undo the locknut which fixes the antenna to the roof panel and remove the antenna.
  5. Replace the antenna.

• What is the correct sequence to replace the 24/12V voltage converter?

  1. Put the machine in service position.
  2. Remove the cover from behind the operator's seat (five clips).
  3. Detach the electrical cables to the converter.
  4. Remove the converter from its bracket.
  5. Replace the converter.

  Note: The voltage converter is available in two versions, one of which has fragile plastic brackets; be careful when changing it.

Overloading System

• What is the correct sequence to check the overloading system?

  1. Lift a load approximately 1 m.
  2. Run out the boom and check that the overloading system is activated.

• What anti-tip system operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the anti-tip system's operation (automatic control).
  2. Check the anti-tip system's operation (manual control).
  3. Check the anti-tip control unit's wiring (automatic control).
  4. Check the anti-tip relay's wiring (manual control).
  5. Check the anti-tip system's function.
  6. Check the anti-tip system's wiring.
  7. Check the anti-tip bypass's operation.
  8. Check the telescopic extension bypass's operation.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

Camera Monitor

• What is the correct sequence to remove and reinstall the closed circuit TV camera?

  1. Disconnect the cable.
  2. Remove the bolt and nut to release the camera.
  3. Re-install the camera by reversing the removal procedure.

• What is the correct sequence to remove and reinstall the CCTV monitor?

  The monitor is placed inside the cab, on the operator's left side.

  1. Disconnect the cable.
  2. Remove the bolt to release the monitor with its support.
  3. Remove the bolt and nut to release the monitor from the support.
  4. Re-install the monitor by reversing the removal procedure.

Other Electrical & Control Systems procedures

• What is the correct sequence to replace the accelerator pedal?

  1. Put the machine in service position.
  2. Remove the three screws that hold the accelerator to the floor.
  3. Undo the accelerator pedal connector.
  4. Remove the accelerator pedal.
  5. Install in reverse order.

  Note: The accelerator pedal is factory calibrated, but may need to be recalibrated after replacement.

• What is the correct sequence to calibrate the electric load scales?

  1. Operate the trolley up and down a few times to remove any mechanical tension.
  2. Operate the machine for a few minutes before zero adjustment and weight calibration take place.
  3. Navigate to the service menu to select the function to calibrate, then press Enter.
  4. Enter the calibration code, obtained from the machine manufacturer's support (the code determines which service menu is activated: Diagnostics, Initiation or Calibration).
  5. Select SCALE by scrolling with the arrow keys and confirm with Enter.
  6. Unload, operate the trolley up and lower it slowly to about 1 metre above the ground, then reset to zero in menu 1(2).
  7. Load with a known weight (preferably a frequently used loading weight or close to the machine's maximum load), adjust to the correct weight, lower the trolley slightly, and confirm the weight in menu 2(2); a value for maximum lift capacity must be set in setup for the weight to be adjustable.

  Note: The mast should be in a vertical position and the fork carriage centred for weighing, calibration and taring.

• What is the correct sequence to calibrate the electronic throttle control accelerator pedals?

  1. Select calibration of the electronic throttle control from the setup menu (a service code is required for access).
  2. Press the right front pedal down completely and confirm, then release the right front pedal completely and confirm.
  3. If the machine has hydrostatic transmission or inching, press the left front pedal down completely and confirm, then release the left front pedal completely and confirm.
  4. If the machine has a rotating or reversible driver's seat, press the right rear pedal down completely and confirm, then release the right rear pedal completely and confirm.
  5. If the machine has hydrostatic transmission or inching and a rotating seat, press the left rear pedal down completely and confirm, then release the left rear pedal completely and confirm.

• What is the correct sequence to replace the reversing alarm?

  1. Put the machine in service position.
  2. Unplug the connector from the reversing alarm.
  3. Remove the two Allen screws securing the reversing alarm.
  4. Replace the reversing alarm.

• What is the correct sequence to replace the operating time gauge?

  The exact panel removed to access the gauge varies by cab type, but the underlying sequence is common.

  1. Put the machine in service position.
  2. Remove the screws that hold the relevant panel(s) in place and remove the panel(s): on some cabs the rear right panel and then the instrument panel, on others the single panel covering the gauge.
  3. Unplug the connector from the operating time gauge.
  4. Remove the two screws on the rear piece of the operating time gauge.
  5. Replace the operating time gauge.
  6. Fit in reverse order.

• What is the correct sequence to replace one of the machine's electronic control units (ECUs)?

  Applies to each of the machine's programmable control units (general, hydraulics, steering, and the display terminal); the exact covers removed to reach the unit vary slightly by unit.

  1. Put the machine in service position.
  2. Remove the covers needed to access the control unit (behind the driver's seat for the general/hydraulics/steering units, or the steering wheel centre cover and panel covers for the display terminal).
  3. Upload the parameters from the existing control unit using the manufacturer's diagnostic software.
  4. Unplug the connectors from the control unit.
  5. Remove the two screws securing the control unit.
  6. Replace the control unit.
  7. Fit in reverse order.
  8. Download the parameters and software to the new control unit using the manufacturer's diagnostic software.

  Notes:

  • Before removing the old control unit, upload its parameters using the manufacturer's diagnostic software.
  • After fitting the new control unit, download the correct program and all parameters (settings and calibrations) to it using the manufacturer's diagnostic software; contact the machine manufacturer for the correct program if needed.

• What is the correct sequence to reset the service indicator?

  1. Put the machine in service position.
  2. Navigate to the service menu and press Enter.
  3. Enter the code for resetting the service indicator, obtained from the machine manufacturer's support.
  4. Reset the service indication by pressing Enter; NEXT SERVICE changes to the given interval.
  5. To change the length of the service interval, set the desired interval with the plus and minus keys.

  Confirmed across independent manufacturers’ manuals.

• What is the correct sequence to read out an error code from the display?

  Always use the error code menus for reading out error codes, otherwise there is a risk of missing error codes.

  1. Turn the start key to position I.
  2. Navigate to the service menu and press Enter.
  3. When the safety menu is shown, hold Enter pressed in for at least two seconds.
  4. Read the error code list shown on the display; scroll between error codes with the arrow keys.
  5. Note the error code number to avoid forgetting it, along with the error code level, error cause symbol, and affected function symbol.
  6. Use the error code tables to find more information about the error code.
  7. After taking the recommended action, check that no active error codes remain for the function in question.

  Note: In case of error codes of level WARNING or STOP, serious machine damage may result if the engine is started; do not start the engine until the cause of the error code has been identified or repaired.

• What is the correct sequence to drive the machine to service by bypassing the transmission's neutral safety interlock in an emergency?

  Applies only when the operator's-seat safety switch is not working, preventing any travel direction from being selected.

  1. Release the load.
  2. Activate the switch for bypassing.
  3. Select the travel direction.
  4. Drive the machine to service, limiting speed to 10 km/h.

  Note: Bypassing disengages the safety interlocks entirely; no safety system is engaged, so there is a risk of tipping and rolling over. Only use bypassing in emergency situations.

• What is the correct sequence to check the starter motor's brushes?

  1. Thoroughly clean the commutator.
  2. Check the wear and contact condition of the brushes.
  3. If necessary, replace the complete brush holder with one of the same type.

• What is the correct sequence to remove a warning alarm (reverse or front)?

  Applies to the reverse warning alarm, the standard front warning alarm, the optional front warning alarm, and the supplementary alarm if fitted, which are all removed the same way at their respective mounting points.

  1. Disconnect the electrical leads.
  2. Remove the nut and bolt.
  3. Remove the other bolt, if present, to release the alarm from the chassis.

• What is the correct sequence to remove the main 100A disconnect breaker?

  1. Kill the engine.
  2. Remove all keys and remove the positive cable from the battery.
  3. Remove the cover to release the two main disconnect breakers.

  Note: Electrocution hazard: all electrical components should be serviced only by qualified personnel, complying with all local and federal codes; ensure all electrical power sources are disconnected and locked/tagged out, the engine has stopped, all ignition keys are removed, and the positive cable is removed from the battery.

• What instrument and warning-lamp operations are checked during the 500-hour Type A preventive maintenance service?

  There are four preventive maintenance cards (A, B, C, D) covering the machine's complete maintenance plan, on a 500-hour frequency, cycling in the order B-A-B-C-B-A-B-C-B-D before repeating. Service times assume normal operating conditions and may vary with type of use, road surface, and environment.

  1. Check the tachometer's operation.
  2. Check the hour meter's operation.
  3. Tighten the indicator lamps and selector switches on the dashboard.
  4. Check the fuel level indicator's operation.
  5. Check the consent traffic-light's operation.
  6. Check the consent traffic-light's wiring.
  7. Check the alternator warning lamp.
  8. Check the lights warning lamp.
  9. Check the working lights warning lamp.
  10. Check the reversing buzzer's operation.
  11. Check the horn's operation.

  Note: Maintenance must be carried out only by qualified, authorised personnel, working in conditions of maximum safety.

• Checking a suspected cable during troubleshooting

  1. Refer to the appropriate circuit diagram, and check the connections and any joints of the suspected cable.
  2. Disconnect the connector from both the control unit and the component.
  3. Connect the other end of the cable to a point on the frame structure where the cable touches the metal surface without a film of paint or coating.
  4. Use a multimeter to measure the cable resistance between the cable and the machine frame.
  5. The cable is intact if the multimeter shows constant resistance.

  Note: De-energise the electric system first, per the machine's safety instructions for electric systems.

• Checking and cleaning the brake resistors and transformers on a rubber tyred gantry crane

  1. Isolate the brake resistors and transformers from the power supply.
  2. Open the covers of the brake resistors and transformers.
  3. Remove dust from the components.
  4. Check the electrical connections of the brake resistors for oxidation.
  5. Clean the electrical connections of the brake resistors.
  6. Check the tightness of the electrical connections of the brake resistors.
  7. Check the insulation of the cables visually.
  8. Close the covers of the brake resistors and transformers.

  Note: The electric systems must be serviced and repaired by trained service personnel; ensure the electric system is de-energized before commencing work. The components may be hot; wait for them to cool down before starting. The maintenance procedure releases dust from the surface of the components: use personal protective equipment such as gloves, safety goggles and a breathing mask. Brake resistors convert braking energy to heat, and are located, together with the transformers, on the roof of the electrical-equipment house.

• Changing the grease in the secondary gearbox of a motor-driven cable reel

  1. Remove the lubricating grease.
  2. Clean the inside with a brush and grease solvent.
  3. Refill the gearbox with new grease.
  4. Re-assemble, using a new seal between the two flanges.

  Note: A replacement kit with grease, seals, screws and bolts must be available before starting. Access to the secondary gearbox requires first removing the perforated plate around the coupler and the motor-coupler unit (fixed with 2 bolts CHC M10 and 2 nuts HM10), or, on a different case type, the motor-coupler unit plus the secondary gearbox.

• Replacing the input gear set on a motor-driven cable reel's additional gearbox

  1. Remove the snap ring.
  2. Remove the pinion.
  3. Replace the seals.
  4. Carry out the operation in reverse to reassemble.

  Note: A replacement kit with grease, seals, screws and bolts must be available before starting. This procedure does not apply to type 55. Access to the interior of the additional gear unit is as for the grease change procedure.

• Inspecting and maintaining the slip ring assembly of a motor-driven cable reel

  1. Remove the slip ring cover.
  2. Check the connections.
  3. Check that the screws and threaded rods of the slip ring are well tightened.
  4. Check that the hub slip ring is well tightened on the driving shaft.
  5. If the rings are marked, slightly pitted, or have a large carbon deposit, polish them with 320-grade emery cloth.
  6. Clean the insulators.
  7. Remove dust from the assembly.
  8. Check the brush wear (replace if less than 2 mm), the quality of brush-to-ring contact, and the position of the brushes on the rings.
  9. Refit the cover and its seal, changing the joints if they show signs of wear, and tighten to 7 N.m.

  Note: Before opening the cover, be sure that the slip ring is de-energized.

Looking for general maintenance tips and checklists? See Electrical & Control Systems.