1.1 On The bus speed signal has exceeded the maximum or minimum limit (a short circuit of the wiring is possible). The tachograph does not work (if there is a fault between the sensor and the tachograph). Cruise Control does not work (only for a motor with a single-stage overpressure valve). Measurement parameters with the diagnostic tool: in the event of this malfunction, the speed in the control unit remains constant at a value of 5 km / h. Reading the fault memory of the control system: if the fault is occasional, check that the connectors are not fixed. If the fault is actual, carry out the following checks: a). if the tachograph does not operate, monitor the electrical wiring and connectors between the sensor and the tachograph; b). if the tachograph is working, check the correct installation, cleanliness and working clearance of the sensor. If the fault persists, monitor the electrical wiring and connectors between the sensor and the control unit (pin B74) through the bushing B, pin 13. The fault is recorded only when the bus moves and only if the circuit is shorted. If no signal is received, then the control unit does not record any fault and "believes" that the bus is standing.

 

1.2 Not used

 

1.3 On (single-stage valve) does not light (for a two-stage valve) Invalid signal from the buttons of the Cruise Control function. The side drive and the idling speed setting are not valid. Status parameters with the diagnostic tool: monitor the signals from individual switches . Control the resistance of the multimeter directly on the connector of the lever switch at the switch causing the fault. If the button is OK, monitor the cable between the connector of the lever switch and the control unit (terminal B61) through the bushing E, terminal 32 for the switch SET-, between the connector of the lever switch and the control unit (terminal B79) through the bushing E, terminal 34 for the switch SET +, between the connector of the lever switch and the control unit (terminal B59) through the bushing E, terminal 33 for the RESUME switch and between the connector of the lever switch and the control unit (terminal B60) through the bushing E, pin 31 for the switch OFF. The unreliability of the signal is recorded if the signal comes simultaneously from the switches SET and SET + or from the switches RESUME and OFF.

 

1.4. Short circuit on the potentiometer of the fuel feed pedal. Decreased power. With the fuel feed pedal free, the idle speed reaches its highest value (about 1100 rpm). When the fuel pedal is depressed, the engine speedily and uncontrollably increases the speed (approximately 2600 rpm) .Measurements with the diagnostic tool: confirm the correct function of the potentiometer between 0% and 100%. If it is not reached reading the parameters to confirm the correct functioning of the potentiometer, measure the multimeter with its intactness (R and 1.0 kΩ between terminals 2 and 3 of the pedal connector); to control the linear change of resistance, depending on the depression of the pedal between the extreme positions between the terminals 1 - 3 and the terminals 2 - 3 of the pedal connector. If the potentiometer is OK, monitor the cables between the pedal connector, pin 1 and the control unit (pin B83) through the bushing B, terminal 36, between the pedal connector, pin 2 and the control unit (pin B55) through bushing B, terminal 35 and between the pedal connector, the terminal 3 and the control unit (output B81) through the bushing B, terminal 34.

 

1.4 Lit The loss of the signal from the potentiometer of the accelerator pedal (an open circuit is possible). Decreased power. The idling speed is increased at any position of the fuel delivery pedal (approx. 1100 rpm) .Measurement parameters with the diagnostic tool: confirm the correct functioning of the potentiometer between 0% and 100%. If it is not reached reading the parameters to confirm the correct functioning of the potentiometer, measure the multimeter with its intactness (R and 1.0 kΩ between terminals 2 and 3 of the pedal connector); to control the linear change of resistance, depending on the depression of the pedal between the extreme positions between the terminals 1 - 3 and the terminals 2 - 3 of the pedal connector. If the potentiometer is OK, monitor the cables between the pedal connector, pin 1 and the control unit (pin B83) through the bushing B, terminal 36, between the pedal connector, pin 2 and the control unit (pin B55) through bushing B, terminal 35 and between the pedal connector, the terminal 3 and the control unit (output B81) through the bushing B, terminal 34.

1.5 lit (single-stage valve) is not lit (in the case of a two-stage valve) Clutch switch: ineligible Crisis Control signal / side drive is not working. Status parameters using the diagnostic tool: confirm the correct operation of the switch. Check the LED test lamp under the plastic protective cover (with the free clutch pedal, the test lamp should be on). If the sensor is in order and correctly laid, check the electrical wiring, connectors and the correct adjustment of the sensor (distance from the pedal: 1 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. Cruise Control does not work because the control unit "believes" that the pedal is constantly depressed. ATTENTION: make sure the cable is routed so that it does not come to its compression and damage when the clutch pedal is depressed.

 

1.6 lights Brake switches: unreliable signals between the primary and secondary switch. Brake lights must not light up. Cruise Control does not work. The status parameters with the diagnostic tool: confirm the correct and timely activation of both brake switches. With a multimeter, check the short circuit on the connector of the switches. If the switches are not damaged, check the cables between the switch connector, pin 4 and the control unit (pin B76) and between the switch connector, pin 2 and the control unit (pin B80) via IBC and bushing B, pin 31.

 

1.7 does not illuminate Unreliable signals between the brake pedal and the fuel pedal or the simultaneous pressing of both pedals. The engine is lowered to the idling limit. Status parameters using the diagnostic tool: check the signal from the potentiometer after releasing the accelerator pedal. It is possible that the driver could also press both pedals at the same time. If the brake pedal is depressed simultaneously with the fuel pedal, the engine speed decreases, while holding the fuel pedal at the idle speed limit so that it is possible to stop the bus, even though the feed pedal fuel is locked in the pressed position (safety mode). In spite of this, it is allowed to "gas" with the brake pedal depressed without the safety mode.

 

1.8 not illuminated Defective control lamp on the optical panel. Power reduction (only for a motor with a single-stage overpressure valve). The indicator lamp never lights 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 12 and 13 of the module. If the light bulb is OK, check the cable between the light bulb terminal 12 and the control unit (pin B28) through the bushing B, pin 7 and between the bulb terminal 13 and the control unit (pin B28) through the bushing B, pin 8. The correct operation of the test lamp is a vital view to the problem-free functioning of the system. Explain to the user the procedure for correctly confirming the activity of the warning lamp (if the system does not have a malfunction, after turning on the key, the test lamp should light up for about 2 seconds, then go out).

 

1.9 On (single-stage valve) does not light (for a two-stage valve) Motor (exhaust) selector: an unreliable signal or loss of interconnection, depending on the control of the motor brake. The exhaust brake is activated only after the pedal is depressed on the floor of the cab or after pressing the pedal will not turn on and can only be operated in the next two selector positions. Status parameters using the diagnostic tool: check the signal from the engine brake switch. If the signal does not come from the selector to the control unit, check with the multimeter that the selector switch is correctly connected between terminals 6 and 8 of the connector. If the selector is OK, check the cables between the selector connector, terminal 6 and the control unit (output B38) through the bushing E, terminal 36 and between the selector connector, the terminal 8 and the control unit (output B22) through the bushing E, terminal 35.

2.1 lit Coolant temperature sensor: short circuit in positive connection line, short circuit to ground or open circuit. Arrow of temperature indicator in limit position, the indicator light is on. Measuring parameters with diagnostic tool: in case of this fault, the temperature read in the parameters is half than the temperature of the engine oil. Check with a multimeter for sensor intactness between terminals 1 and 2 (at a temperature of 20 ° C, the resistance is approximately 2.5 kΩ). If the sensor is in order to monitor the cables between the sensor, pin 1 and the control unit (pin C18) and between the sensor, pin 2 and the control unit (pin C36).

 

2.2 lit The air temperature sensor on the intake side of the motor: short circuit in positive connection line, short to earth or open circuit. No detectable change by the bus driver. Measuring parameters with diagnostic tool: in case of this fault, the temperature read in the parameters is unchanged at 30 ° C. If the air temperature remains unchanged at 30 ° C, check with a multimeter that the sensor is intact between terminals 1 and 2 (at a temperature of 20 ° C, the resistance is approximately 2.5 kΩ). If the sensor is in order to monitor the cables between the sensor, pin 1 and the control unit (pin C21) and between the sensor, pin 2 and the control unit (pin C29).

 

2.3 lit Fuel temperature sensor: short circuit in positive connection line, short circuit to ground or open circuit. No detectable change by bus driver. Measuring parameters with diagnostic tool: in case of this fault the temperature read in the parameters is unchanged at 20 ° C . Check with a multimeter for sensor intactness between terminals 1 and 2 (at a temperature of 20 ° C, the resistance is approximately 2.5 kΩ). If the sensor is in order to monitor the cables between the sensor, pin 1 and the control unit (pin C17) and between the sensor, pin 2 and the control unit (pin C34).

 

2.4 flashing The engine intake air pressure sensor: a short circuit in the positive connection line, a short to ground or an open circuit or supply current has exceeded the maximum / minimum value. There is no recognizable change by the bus driver. Power reduction (only for a motor with a single-stage overpressure valve). Measurement parameters with the diagnostic tool: in the event of this fault, the pressure read in the parameters is unchanged at a value of 1600 bar. Check the cables between the sensor, terminal 3 and the control unit (terminal C10) and between the sensor, pin 4 and the control unit (terminal C28). The air pressure sensor is an integral part with an air temperature sensor. If the electrical part of the sensor connection is OK, check the proper operation of the turbocharger WASTEGATE discharge valve.

 

2.5 not lit Atmospheric pressure sensor (installed in the control unit): short circuit in the positive connection line, short to earth or open circuit. No detectable change by the bus driver. Measurement parameters with the diagnostic tool: in case of this fault, the pressure read in the parameters is unchanged at a value of 970 bar. Contact the Help Desk and follow their instructions if there is a possible replacement of the control system. The sensor is installed in the control unit and is not replaced separately. The possible painting of the engine / control unit can cause poor atmospheric pressure measurements.

 

2.6 lit Engine oil pressure sensor: short circuit in positive connection line, short to earth or open circuit. Arrow of temperature indicator in limit position, the indicator light is on. Power reduction (only for a motor with a single-stage overpressure valve). Measurement parameters with the diagnostic tool: in the event of this fault, the pressure read in the parameters is unchanged at a value of 60 bar. Check the cables between the sensor, terminal 3 and the control unit (terminal C9) and between the sensor, pin 4 and the control unit (terminal C35). The engine oil pressure sensor is an integral part with the engine oil temperature sensor.

 

2.7 lit Engine oil temperature sensor: short circuit in positive connection line, short to earth or open circuit. No detectable change by bus driver. Measurement parameters with diagnostic tool: in case of this fault, the temperature read in the parameters is fixed at 120 ° FROM. Check with a multimeter for sensor intactness between terminals 1 and 2 (at a temperature of 20 ° C, the resistance is approximately 2.5 kΩ). If the sensor is in order to monitor the cables between the sensor, pin 1 and the control unit (pin C19) and between the sensor, pin 2 and the control unit (pin C33). If the engine oil temperature is too low, the engine speed is limited to the temperature ). The engine oil temperature sensor is an integral part with the engine oil pressure sensor.

 

2.8 the fuel preheating relay in the fuel filter is off). Heating is always on. The batteries are discharged. b). Heating can not be turned on. Possible clogging of the fuel filter due to the separation of paraffin from the fuel at T <-15 ° C. Active diagnostics using a diagnostic tool. Check the cables between the relay terminal 85 and the control unit (output B2) through the bushing E, terminal 38 and between the relay terminal 86 and the control unit (terminal B36) through the bushing E, terminal 29.a). Failure of 2.3 can be registered because the fuel is too hot.

 

2.9 The incandescent relay is hot). Resistance of glow without power. Perhaps the wrong cold start of the engine and increased smoke when starting the engine. b). The resistance of the glow is constantly under tension. Possible damage to the heat resistance and rapid discharge of batteries. Active diagnostics using a diagnostic tool. Check the cables between the relay terminal 85 and the control unit (terminal B4) and between the relay terminal 86 and the control unit (terminal B20).