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IVECO Bus Fault Codes (part 3)


7.1 does not light The program limiter button on the dashboard. The speed limit on the driver's request does not work or the bus continuously moves at a limited speed. Status parameters using the diagnostic tool: check the button activation. If the signal does not come to the control set-up, check with the multimeter that the buttons between terminals 2 and 3 are correctly connected. If the button is OK, check the cable intact between pin 3 of the button and the control unit (pin B26) through the bushing B, pin 22.

 

7.2 OFF (for a single-stage valve) the CAN line is lit (for a two-stage valve). Incorrect functioning of the immobilizer. Check the electrical wiring, connectors and line impedance (120 ohms). The immobilizer is blocked or does not allow the engine to start.

 

7.5 does not light Engine brake warning lamp: short to ground or open circuit. The control lamp sometimes does not light up after the ignition key is turned on or remains lit after the ignition key is turned off. Active diagnostics using the diagnostic tool. If the test lamp does not work during active diagnostics, check the bulb's integrity between terminals 2 and 5 of the module. If the light bulb is OK, check the cable between the light bulb terminal 5 and the control unit (pin B47) through the bushing B, pin 21.

 

7.6 does not light Engine low pressure warning lamp: short to ground or open circuit. The control lamp sometimes does not light up after the ignition key is turned on or remains lit after the ignition key is turned off. Active diagnostics using a diagnostic tool. If the test lamp does not operate during active diagnostics, check the bulb's integrity between pins 2 and 4 of the pointer. If the light bulb is OK, check the cable between pin 2 and the control unit (pin B63) through the bushing B, pin 17.

 

7.7 OFF Lubrication signal of engine lubricant: short to ground or open circuit. Wrong declaration of engine lubricant pressure. Active diagnostics using the diagnostic tool. Check the cable between the indicator terminal 6 and the control unit (terminal B66) through the bushing B, terminal 18.

 

7.8 does not light Engine coolant temperature warning lamp: short to ground or open circuit. The control lamp sometimes does not light up after the ignition key is turned on or remains lit after the ignition key is turned off. Active diagnostics using the diagnostic tool. If the test lamp does not operate during active diagnostics, check the bulb integrity between pins 1 and 4 of the pointer. If the light bulb is OK, check the cable between pin 1 and the control unit (pin B65) through the bushing B, pin 15.

 

7.9 does not light Engine coolant temperature signal: short to ground or open circuit. Incorrect engine coolant temperature announcement. Active diagnostics using the diagnostic tool. Check the cable between terminal 3 of the indicator and the control unit (terminal B6) through the bushing B, terminal 16.

 

8.1 flashing Controlling the fuel pressure control: the fuel pressure in the battery is greater or less than the value calculated by the control unit. A large reduction in power. Measuring parameters with the diagnostic tool: compare the actual and calculated pressure. In the normal state, at idle speed of the unloaded engine, the difference should be less than 5%. If the difference is greater than 5%, carry out the following checks regarding fault 8.1.

 

8.1 flashing Adjusting the fuel pressure control: insufficient fuel in the tank. A large reduction in power. Control the fuel level in the tank.

 

8.1 flashing Controlling the fuel pressure control: the fuel inlet sieve is partially clogged with sewage or deformed by overheating. A large reduction in power. Check the correct operation of the manual priming pump on the coarse fuel filter. If the pushbutton pump button remains after pressing in its lower position due to low pressure, remove and monitor the sieve from the fuel tank. If the sieve is in order, replace the coarse fuel filter. If sawdust has fallen (in case of intervention carried out by the superstructure on the fuel tank), carry out a thorough cleaning of the tank. The malfunction can not come back like this again with the following sawdust, which may have remained in the tank.


8.1 flashing Controlling the fuel pressure control: air access at the inlet of the feed pump pump. A large reduction in power. Check the seal (O-ring) and the correct connection of the fuel hoses between the tank and the booster pump (the clamps must be properly fixed and the connections well established).

 

8.1 flashing Controlling the fuel pressure control: leaking fuel from the connections or hoses at the outlet of the pumping gear pump. A large reduction in power. Check the seal (O-ring) and the correct connection of the fuel hoses at the outlet from the pumping gear pump (the clamps must be correctly fixed and the connections well established). Visually monitor the intactness of the hoses of the low-pressure part of the fuel system.

 

8.1 flashing Adjusting the fuel pressure control: possibly a bad signal from the fuel pressure sensor in the battery. A large reduction in power. Check the cables between the sensor connector, pin 1 and the control unit (pin C20), between the sensor connector, pin 2 and the control unit (pin C27) and between the sensor connector, terminal 3 and the control unit (output C12). After all possible causes have been eliminated, replace the sensor.

 

8.2 flashing The fuel pressure sensor in the battery: a short in the positive branch of the connection, a short to ground or an open circuit. Engine shutdown (only for a motor with a single-stage overpressure valve). A large reduction in power (only for a motor with a two-stage overpressure valve). Check the cables between the sensor connector, terminal 1 and the control unit (output C20), between the sensor connector, terminal 2 and the control unit (terminal C27) and between the sensor connector, terminal 3 and the control unit (output C12). After all possible causes have been eliminated, replace the sensor.

 

8.3 flashing Pressure regulator: short circuit in the positive connection branch, short to earth or open circuit. A large decrease in power. Check that the pressure regulator is correctly connected to its connector. Check with a multimeter the intactness of the electromagnetic valve of the regulator (R «3,2 Ohm). If the regulator is OK, check the cable intact between the regulator connector and the control unit (terminals C5 and C7).

 

8.4 flashing Intervention of a two-stage overpressure valve. A large reduction in power. Perform monitoring related to faults 8.2 and 8.3. Only in the case of an engine with control units programmed for a two-stage overpressure valve. If you simultaneously register this fault and fault 8.1, first eliminate the cause of fault 8.4, because fault 8.1 in this case is its consequence. In the case of fault 8.4 (the EDC indicator lamp does not light) for 210kW and 240kW motors with a single-stage overpressure valve, contact the Help Desk.

 

8.5 flashing Malfunction of the minimum-maximum pressure in the accumulator. The motor switches off. Replace the overpressure valve. If the fault persists, carry out the monitoring associated with faults 8.2 and 8.3. Only in the case of an engine with control units programmed for a two-stage overpressure valve.

 

9.3 flashing Communication problems with the immobilizer control unit: a short to ground or an open data bus circuit between the engine and the immobilizer. The engine can not be started. Possible fault recording 7.2. Check the electrical wiring, connectors and line resistance (120 ohms). Diagnose the faults of the immobilizer using the diagnostic tool. If a bad key is used, the immobilizer warning light (fault not in the EDC control unit) also flashes.

 

9.4 ON The main relay does not open. The control unit is permanently energized and the EDC indicator lamp lights up even after the key is turned off. There is a rapid discharge of batteries. Check the electrical wiring and connectors. Try removing and reinstalling the main fuse. Cancel fault memory. If this fault persists, contact the Help Desk for approval of a possible replacement of the control unit. The main relay is an integral part of the control unit and is not separately replaced.

 

9.6 lights Too often the interruption of the recording of operation data. A large decrease in power. Check and confirm if there is a trip on the move (a moving bus with gear engaged). Check the cable between the ignition switch (+15) and the control unit (terminal B2). Cancel the fault memory and check again. If the motor trips normally and this fault persists, contact the Help Desk for approval of a possible replacement of the control system. The motor will not shut down before the preset interval has elapsed after the ignition key is turned off.

 

9.7 lit Internal malfunction of the control unit in the sensor supply circuit. Unnatural stroke of the motor due to incorrect power supply of the sensors. Reduce the power. Delete the fault memory. If this fault persists, contact the Help Desk for approval of a possible replacement of the control system. It is possible to register faults of different sensors supplied by the control system.


Low power when demanding a load. Possible vibration and increased smoke. Possible malfunction 8.1. Low fuel level in the tank. Controlling the level of fuel in the tank. The increased foginess occurs when the insufficient amount of fuel enters the cylinder and the control unit tends to equalize it by extending the period of supply of the injectors.

The fence with the mesh in the fuel tank is partially clogged with sewage or overheating to its deformation. Check the correct operation of the hand pump on the coarse fuel filter. If the pump button remains pulled down due to low pressure, dismantle it and monitor the intake with the grid in the fuel tank. If the fence with the mesh is in order, replace the coarse fuel filter.

Air bubbles at the inlet into the booster pump. Check the O-rings and the connection of the fuel hoses between the fuel tank and the booster pump (the clamps must be on the outside and well fixed).

Leakage of fuel from low pressure connections or hoses at the outlet of the booster pump. Check the O-rings and the connection of the fuel hoses to the outlet from the booster pump (the clamps must be on the outside and well fixed). If the fuel leakage is insignificant, the power will not decrease. To check the sealing rings, remove the hose from the back of the fuel from the tank, airtightly seal it and manually pump the fuel into the low-pressure branch of the system.

Inconsistent fuel return from the battery excess pressure valve. Disconnect the return branch hose and check that there is no explicit return from the overpressure valve.

The engine suddenly turns off (without previous fluctuations) and it can not be started. Interruption of the signal from the ignition switch to the control unit. Check the electrical wiring.

The engine suddenly turns off (without previous fluctuations) and it can not be started. The fuel filter is clogged. Replace the fuel filter. Eliminate the cause of filter clogging (release and clean the fuel tank and fuel system parts before entering the filter, fill the system with clean fuel).

Difficult start of the engine and its low power in all modes. Inoperative high pressure pump. Carry out an engine test (MODUS, IWT, IT2000). After eliminating all possible causes, replace the high pressure pump.

Difficult start of the engine and its low power; the engine does not work for all cylinders. The nozzle valve (shut-off valve) or the solenoid valve core (mechanical part) is locked in the open position. Run an engine test (MODUS, IWT, IT2000). If there is no diagnostic tool, you can simply recognize that the injector is not working properly. During filling, no pulsation is felt in this high-pressure pipeline. If there is such a minor return that prevents the nozzle from opening, but does not reset the flow limiter, no fault is detected by the control unit. If the flow limiter intervenes, the control unit will register fault 8.1.

At full load, engine power is reduced and fault 8.1 is declared. If the engine is switched off, it can be restarted and operates normally only at low speed and low load. The jam is blocked open (on occasion), the flow limiter intervenes. If there is no diagnostic tool, you can simply recognize that the injector is not working properly. During filling, no pulsation is felt in this high-pressure line. If the flow limiter is intervening, the control unit will register fault 8.1.

Starting the engine lasts at least 20 seconds, huge clouds of white smoke emerge from the exhaust silencer, the smell of fuel. The device is locked open (no return). If there is no diagnostic tool, you can simply recognize that the injector is not working properly. During filling, no pulsation is felt in this high-pressure pipeline. Normally, if there are such signs, instinctively stops with the engine starting. Nevertheless, due to inertia, it is possible to start the engine, and so to get to the IVECO service workshop. By inertia, the engine will start and run on one cylinder less, gradually on small parts its smoke also decreases, until it is completely eliminated.

The engine runs one cylinder less, the control unit does not record any malfunction. The junction is locked closed. If there is no diagnostic tool, you can simply recognize that the injector is not working properly. During filling, no pulsation is felt in this high-pressure pipeline.

The Cruise Control / Side Drive is not deactivated by depressing the clutch pedal. By pressing the clutch pedal with the active Cruise Control function, the engine rises to the maximum limit. Clutch Sensor: There is no signal. Read the parameters (MODUS, IWT, IT2000) when the clutch pedal is fully depressed and released. If the sensor is in order and properly laid, check the electrical wiring, connectors and correct sensor adjustment (distance from the pedal: 1 to 3 mm). If no signal is received to depress the pedal, the control unit does not notify the cause and considers this condition to be normal. By depressing the clutch pedal with the Cruise Control active, the engine rises to the maximum limit with a view to the fact that the control unit tends to regulate the lower engine load in order to hold the preset speed (revolutions).