MID 144 Volvo FH Vehicle Electronic Control Unit Fault Codes

Fault codes

Parameter

Description

Vehicle control unit (VECU)

MID 144 PID 29 FMI 3

Accelerator pedal sensor №2. (only for dual cars)

  The voltage of the signal from the pedal sensor is higher than 4.3 V. A break in the ground wire. Closing the signal wire to a higher voltage. Faulty sensor or idle switch 3   accelerator pedals .

MID 144 PID 29 FMI 4

Accelerator pedal sensor №2. (only for dual cars)

The signal voltage from the pedal sensor is below 0.4 V. Breakage of the signal or supply wire. Shorting the signal wire to ground. The pedal sensor may be faulty.

MID 144 PID 46 FMI 0

Air pressure in the primary receiver (only for cars with air suspension)

The pressure in the air suspension receiver is above normal. The compressor discharge valves in the compressor head are faulty, the wiring of the compressor discharge solenoid valve in the dryer is damaged. Damaged, dirty or clogged compressor discharge valve in the drier. The air pressure sensor is faulty (the sensor is located behind the instrument panel on the right).

MID 144 PID 46 FMI 1

Air pressure in the primary receiver (only for cars with air suspension)

The vehicle control unit receives a signal from a sensor with a voltage below 3.1 V (corresponds to 9.7 bar) for the older version and below 2.6 V (corresponds to 8.0 bar) for a newer version. Air pressure below normal. Air leaks, clogged, damaged air lines or air suspension components.

MID 144 PID 46 FMI 3

Air pressure in the primary receiver (only for cars with air suspension)

The vehicle control unit receives a signal from a sensor with a voltage higher than 4.5 V (corresponding to 15 bar). Broken wire connection to ground. Shorting the signal wire to a higher voltage. Air pressure sensor may be faulty.   (the sensor is located behind the instrument panel on the right).

MID 144 PID 46 FMI 4

Air pressure in the primary receiver (only for cars with air suspension)

The vehicle control unit receives a signal from a sensor with a voltage above 0.5 V. Breakage of the signal or supply wires. Shorting the signal wire to ground. Air pressure sensor may be faulty.

MID 144 PID 46 FMI 14

Air pressure in the primary receiver (only for cars with air suspension)

Manifests itself   when the signal from the vehicle control unit is sent to a dehumidifier, and   air pressure in the system continues to increase. Damaged or blocked tube control valves of the compressor from the desiccant. Faulty valves in the compressor head (jammed in the closed position). Damaged wiring between the vehicle control unit and the discharge valve on the water dryer. Damaged, dirty or clogged compressor discharge valve in the drier. The air pressure sensor is faulty (the sensor is located behind the instrument panel on the right). The safety valve should go off. If the safety valve is clogged and does not work, the compressor head seals may fail and large amounts of air from the compressor may enter the engine cooling system.

MID 144 PID 84 FMI 2

Car speed signal

The big difference between the speed signals coming from the tachograph (by data channel   SAE J1939   or to the contact of the vehicle control unit PB6) and speed signals from the wheel rotation sensors   (ABS) .Before troubleshooting in the system of the vehicle control unit, read the system fault codes   ABS / EBS   and eliminate the causes of their manifestation. Also possible faulty wiring or signals from the tachograph is not true. Perhaps there were manipulations with the speed sensor or with the wiring between the speed sensor on the gearbox and the tachograph.

MID 144 PID 84 FMI 14

Car speed signal

Tachograph speed signals are not correct. Damaged wiring. Probably defective speed sensor on the gearbox or tachograph ..

MID 144 PID 86 FMI 14

Set speed (cruise control)

Vehicle control unit   (VECU)   does not receive information from the adaptive cruise control unit (ACC)   by data channel   SAE J1939. Breaking or partial damage to the data channel. The ACC unit may be faulty.

MID 144 PID 91 FMI 3

Accelerator pedal position

The voltage of the signal coming to the control unit from the accelerator pedal sensor is higher than 4.3 V. Break in the power or ground wire. Shorting the signal wire to a higher voltage. The pedal position sensor or the pedal # 1 idle switch may be faulty. The sensor and switches are integrated with the accelerator pedal.

MID 144 PID 91 FMI 4

Accelerator pedal position

The voltage of the signal to the control unit from the accelerator pedal sensor is less than 0.4 V. The break in the power or signal wire. Shorting the signal wire to ground. Defective or oxidized contacts in the connectors. Accelerator pedal position sensor may be faulty.

MID 144 PID 91 FMI 5

Accelerator pedal position

The low level signal from the position sensor does not correspond to the signals from the idling switch №1 or №2. Faulty pedal position sensor. Damaged or oxidized pins in connectors.

MID 144 PID 91 FMI 6

Accelerator pedal position

The high level signal from the position sensor does not match the signals from the idling switch No. 1 or 2. Faulty pedal position sensor. Damaged or oxidized pins in connectors.

MID 144 PID 91 FMI 14

Accelerator pedal position

Malfunction in the power circuit. Breakage or partial damage to the power cord.

MID 144 PID 150 FMI 4

Power takeoff

The voltage at the PBV contact of the vehicle control unit with an unused function is below 2.3 V. Break in the power supply wire of the power take-off solenoid valve.Broken wire between the valve and the control unit. Damaged or oxidized pins in connectors. The solenoid valve may be faulty.

MID 144 PID 152 FMI 12

The number of re-installation of the car control unit.

The code is registered in case of an internal failure in the software, and the internal independent function of restarting the vehicle control unit is triggered . The code is informational and is not a fault code.

MID 144 SID 230 FMI 7

Idle switch №1 accelerator pedal

The accelerator pedal is fully released, and the signal from the idle switch does not flow to the vehicle control unit. Break signal or power wires. Shorting the signal wire to ground or positive. Damaged or oxidized pins in connectors. Perhaps afaulty switch integrated with the accelerator pedal .

MID 144 SID 231 FMI 2

Data feed SAE J1939

The control unit does not receive messages over the data channel.   SAE J1939. Breaking or partial damage to the data channel wiring. Damaged or oxidized pins in connectors.

MID 144 SID 231 FMI 12

Data feed SAE J1939

The control unit does not receive messages over the data channel.   SAE J1939. Breaking or partial damage to the data channel wiring. Damaged or oxidized pins in connectors.

MID 144 SID 250 FMI 2

Data feed SAE J1708

Errors in messages on the data channel   SAE J1708. Partial damage to the data channel wiring.

MID 144 SID 253 FMI 2

Gauge EEPROM Memory

Programming error or control unit memory chip is faulty. Try to reprogram the unit (performed only on authorized service stations)

MID 144 SID 253 FMI 14

Gauge EEPROM Memory

Data error Faulty memory chip in control unit or software error.   Try to reprogram the unit (performed only on authorized service stations).

MID 144 PPID 3 FMI 3

Starter relay

Very strong current through the power stage. Short to power plus. Faulty wiring or short circuit in the relay coil.

MID 144 PPID 3 FMI 4

Starter relay

Faulty relay, wire break or short to ground.

MID 144 PPID 61 FMI 7

Retarder switch

Faulty wiring or switch.

MID 144 PPID 69 FMI 3

Buffered Idle Switch

The signal from the buffered idle switch does not match the signal from the idle switch No. 1 accelerator pedal. Signal wire shorted to ground.

MID 144 PPID 69 FMI 4

Buffered Idle Switch

The signal from the buffered idle switch does not match the signal from the idle switch No. 1 accelerator pedal. Signal wire shorted to ground.

MID 144 PPID 70 FMI 4

Power supply for accelerator, brake and clutch pedal switches

The vehicle control unit has detected a voltage lower than 3 V on the power wire of the switches. Shorting of the power wire to ground, short circuit of the signal wire of the accelerator pedal switch, brake or clutch to ground.

MID 144 PPID 71 FMI 4

Power to the retarder and cruise control switches

The vehicle control unit has detected a voltage lower than 3 V on the power wire of the switches. Shorting of the power wire to ground. Closing the cruise control switch signal wire SET + / SET- / RESUME / ON.   A short to ground on the signal wire of the engine brake switch   VCB / EPG.   Short to ground signal wire retarder switch   SET + / SET-. One of the switches may be faulty.

MID 144 PPID 72 FMI 3

Power supply for accelerator pedal sensor and retarder switch

The car control unit has detected a voltage of more than 5.3 V on the power supply wire. A break in the ground wire, a short to a higher voltage, a break in the power wire. The retarder switch or the accelerator pedal sensor may be faulty. Damaged or oxidized pins in connectors.

MID 144 PPID 72 FMI 4

Power supply for accelerator pedal sensor and retarder switch

The vehicle control unit has detected a voltage lower than 4.7 V on the power wire. Shorting of the power wire to ground. The retarder switch or the accelerator pedal sensor may be faulty.

MID 144 PPID 73 FMI 3

Power supply air pressure sensor in the primary receiver (air suspension) and the switch "Dynafleet"

The vehicle control unit has detected a voltage of more than 5.3 V on the power wire. An open circuit of the ground wire, a short circuit of the power wire to a higher voltage, an open circuit of the power wire. The air pressure sensor may befaulty (located behind the instrument panel on the right) or the “Dynafleet” switch.

MID 144 PPID 73 FMI 4

Power supply air pressure sensor in the primary receiver (air suspension) and the switch "Dynafleet"

The vehicle control unit has detected a voltage lower than 4.7 V on the power wire. Shorting of the power wire to ground. The air pressure sensor may be faulty (located behind the instrument panel on the right) or the “Dynafleet” switch.

MID 144 PPID 74 FMI 3

Power supply of engine control unit (EECU) and vehicle control unit (VECU)

Control voltage of relay K2 from the PB15 contact of the vehicle control unit above 1 V. Short circuit to a higher voltage or relay K2 is faulty (located on the central distribution board of the relay and fuses in the middle of the instrument panel)

MID 144 PPID 74 FMI 4

Power supply of engine control unit (EECU) and vehicle control unit (VECU)

The control voltage of the relay K2 from the PB15 contact of the vehicle control unit is below 0 V. There is a wire break with the relay K2 or the relay is faulty.

MID 144 PPID 75 FMI 3

Range Locking

The vehicle control unit registers a voltage higher than 6.5 V. The solenoid valvemay be faulty.

MID 144 PPID 75 FMI 4

Range Locking

The vehicle control unit registers a voltage below 2.3 V at the PB18 contact. A break in the supply wire of the demultiplicator blocking solenoid valve. A short to ground between the solenoid valve and the control unit. The solenoid valve may be faulty (located at the rear of the transmission on the range-cylinder cylinder).Damaged or oxidized pins in connectors.

MID 144 PPID 76 FMI 3

Brake Relay

The vehicle control unit registers a voltage of more than 6.5 V. A short to the power wire or a faulty relay.

MID 144 PPID 79 FMI 3

Range Locking, Solenoid Valve Condition

The vehicle control unit has detected a voltage of more than 6.5 V. Shorting the wire between the relay K8   and car control unit. Possible defective relay K 8   (located on the central distribution board of the relays and fuses in the middle of the instrument panel).

MID 144 PPID 79 FMI 4

Range Locking, Solenoid Valve Condition

The vehicle control unit has detected a voltage of less than 2.3 V. Closing the wire between the relay K8 and the vehicle control unit to ground. Break in the power wire of the relay or wire between the relay and the vehicle control unit. Relay K8may be faulty (located on the central distribution board of the relay and fuses in the middle of the instrument panel).

MID 144 PPID 145 FMI 3

Block switches road information system "Dynafleet".

The voltages on the power wire of the switch box are higher than 5 V. The wiring is damaged or the switch is faulty.   "Dynafleet".

MID 144 PPID 145 FMI 4

Block switches road information system "Dynafleet".

The voltages in the power wire of the switch box are below 0.5 V. The wiring is damaged or the Dynafleet switch is faulty.

MID 144 PPID 265 FMI 3

Power supply vehicle speed sensor on the gearbox

The voltage on the power wire between the vehicle control unit and the speed sensor is above 9 V. Break of the ground wire. Shorting the signal wire to a higher voltage. There may be a speed sensor malfunction.

MID 144 PPID 265 FMI 4

Power supply vehicle speed sensor on the gearbox

The voltage on the power wire between the vehicle control unit and the speed sensor is below 6.5 V. Breakage of the signal or supply wire. Shorting the signal wire to ground. There may be a speed sensor malfunction.

MID 144 PPID 279 FMI 0

Dehumidifier filter

The life of the filter drier, calculated by the control unit of the car, is over.

MID 144 PPID 302 FMI 3

Condition of heating of mirrors

A short to a higher voltage or a faulty relay.

MID 144 PPID 302 FMI 4

Condition of heating of mirrors

Broken wire from relay or faulty relay.

MID 144 PPID 302 FMI 12

Condition of heating of mirrors

Faulty relay.

MID 144 PPID 312 FMI 0

Regeneration air dryer

Very high air flow rate due to air leaks or frequent use of equipment that requires large amounts of compressed air to operate.

MID 144 PPID 312 FMI 7

Regeneration air dryer

The regeneration valve is open for 30 seconds, while the pressure in the pneumatic system has not changed. The dehumidifier muffler is clogged, the regeneration valve is dirty, defective and does not open. Damaged wiring between the control unit and the dehumidifier solenoid valves. Check fuses   F10   or   F6 (depends on the version of electronic equipment). Check for the presence of a 24 volt supply on the black wire of the connector of the solenoid valve of the desiccant.

MID 144 PPID 430 FMI 0

Regeneration air dryer

Very high air flow rate due to air leaks or frequent use of equipment that requires large amounts of compressed air to operate.

MID 144 PSID 1 FMI 7

Retarder switch

The vehicle control unit receives signals from " SET +"   and   "SET-" at the same time. The signal wire is shorted to the power wire or the switch is faulty.

MID 144 PSID 2 FMI 7

Standby idle switch №2 accelerator pedal (only for cars with automatic transmissions)

  When you release the accelerator pedal, the control unit does not receive a signal from the idling switch №2. Open power or signal wire. Shorting the signal wire to plus or ground. Damaged or oxidized pins in connectors. Perhaps a faulty switch integrated with the accelerator pedal.

MID 144 PSID 3 FMI 7

The switch of idling No. 3 (for cars with an additional accelerator, with double management)

The signal in the range of 0-13% of the idle switch does not flow to the vehicle control unit. Open power or signal wire. Shorting the signal wire to plus or ground.Damaged or oxidized pins in connectors. Perhaps a faulty switch integrated with the accelerator pedal.

MID 144 PSID 4 FMI 3

Retarder Switch Lever

The vehicle control unit detects a voltage above 4.8 V. A break in the ground wire.Shorting the signal wire to a plus. Damaged or oxidized pins in connectors. Possibledefective moderator switch lever.

MID 144 PSID 4 FMI 4

Retarder Switch Lever

The vehicle control unit detects a voltage below 0.2 V. An interruption in the supply or signal wire. Closing the signal wire to ground. Damaged or oxidized pins in connectors. Possible defective moderator switch lever.

MID 144 PSID 5 FMI 7

Brake pedal sensor

Error in the signal from the brake pedal sensor. Damaged, oxidized contacts or faulty sensor.

MID 144 PSID 7 FMI 3

Speed threshold 2

On contact   PB2   Vehicle control unit detected abnormally high voltage. Shorting the signal wire to a plus. Oxidation or high resistance. Faulty relay.

MID 144 PSID 7 FMI 4

Speed threshold 2

On contact   PB2   vehicle control unit detected abnormally low voltage. Closing the signal wire to ground. Oxidation or high resistance. Faulty relay.

MID 144 PSID 8 FMI 2

Neutral position

The vehicle control unit has detected that the requested gear does not match the actual one. Defective neutral position sensor on the gearbox.

MID 144 PSID 8 FMI 3

Neutral position

The vehicle control unit has found that when speed is reached   above 50 km / h the neutral state has not changed. Broken wire mass sensor neutral position. Signal wire closure to plus. Oxidation or high resistance.

MID 144 PSID 8 FMI 4

Neutral position

The control unit of the car found that when reaching a speed above 50 km / h, the state of neutral position did not change. Broken wire signal sensor neutral position. Shorting the signal wire to ground. Oxidation or high resistance. 

MID 144 PSID 9 FMI 3

Clutch pedal sensor

The control unit of the car found that the position of the clutch pedal does not change when it reaches a speed above 50 km / h. Broken wire mass sensor. Signal wire closure to plus. Damaged, oxidized contacts or faulty sensor. 

MID 144 PSID 9 FMI 4

Clutch pedal sensor

The control unit of the car found that the position of the clutch pedal does not change when it reaches a speed above 50 km / h. Broken wire signal sensor neutral position. Shorting the signal wire to ground. Oxidation or high resistance.

MID 144 PSID 10 FMI 3

Relay K41 reversing light

An abnormally high voltage is detected at terminal PB4 of the car control unit. Mass wire breakage. Shorting the signal wire to a plus. Oxidation or high resistance.   

MID 144 PSID 10 FMI 4

Relay K41 reversing light

An abnormally low voltage is detected at the PA8 terminal of the car control unit. Closing the signal wire to ground. Oxidation or high resistance.   

MID 144 PSID 11 FMI 3

Relay K42 braking signals

An abnormally high voltage is detected at terminal PB28 of the car control unit. Mass wire breakage. Shorting the signal wire to a plus. Oxidation or high resistance.   

MID 144 PSID 11 FMI 4

Relay K42 braking signals

An abnormally low voltage is detected on the P288 contact of the car control unit. Closing the signal wire to ground. Oxidation or high resistance.   

MID 144 PSID 14 FMI 2

Mistake   Datamax

General failure. Switch off the ignition for at least 1 minute. If the error is active, reprogram the control unit.

MID 144 PSID 19 FMI 3

Status of the parking brake (relay K15)

An abnormally high voltage is detected at terminal PB16 of the car control unit. Mass wire breakage. Shorting the signal wire to a plus. Oxidation or high resistance.   

MID 144 PSID 19 FMI 4

Status of the parking brake (relay K15)

An abnormally low voltage is detected on the PV16 contact of the car control unit. Closing the signal wire to ground. Oxidation or high resistance.   

MID 144 PSID 20 FMI 3

Power takeoff signal

The vehicle control unit registers at the PB16 contact from the solenoid power take-off valve a high voltage or voltage equal to the battery voltage. Shorting the wire between the solenoid valve and the control unit to a higher voltage, or the solenoid valve is faulty.

MID 144 PSID 20 FMI 4

Power takeoff signal

The vehicle control unit registers a voltage below 2.3 V at the PB16 contact from the solenoid power take-off valve. An open wire to the solenoid valve or a wire between the solenoid valve and the control unit. Short to ground between the solenoid valve and the control unit. Solenoid valve defective.

MID 144 PSID 21 FMI 14

CAN 1

By data channel   SAE J1939   CAN 1 networks are transmitted messages that are not supported by the control unit in accordance with the vehicle configuration. Change car configuration.   

MID 144 PSID 22 FMI 14

CAN 2

By data channel   SAE J1939   CAN 2 networks transmit messages that are not supported by the control unit in accordance with the vehicle configuration. Change car configuration.   

MID 144 PSID 23 FMI 3

Regeneration air dryer

The vehicle control unit registers at the contact PB4 or PB3 a higher voltage or voltage equal to the voltage of the batteries. Signal wire closure to plus. Defective solenoid valve defective.

MID 144 PSID 23 FMI 4

Regeneration air dryer

The vehicle control unit registers a voltage below 2.3 V at the PB4 or PB3 terminal. A break in the signal or supply wire. Shorting the signal wire to ground. Oxidation or high resistance. Defective solenoid valve defective.

MID 144 PSID 24 FMI 3

Air dryer, compressor control

The vehicle control unit registers at the contact PB4 or PB1 a higher voltage or voltage equal to the voltage of the batteries. Signal wire closure to plus. Defective solenoid valve defective.

MID 144 PSID 24 FMI 4

Air dryer, compressor control

The vehicle control unit registers a voltage below 2.3 V at the PB4 or PB1 terminal. A break in the signal or supply wire. Shorting the signal wire to ground. Oxidation or high resistance. Defective solenoid valve defective.

MID 144 PSID 25 FMI 1

Air leak

Air flow from the pneumatic system, at speeds above 50 km / h, is higher than the allowable value. Air leaks in the vehicle or trailer system.

MID 144 PSID 200 FMI 9

Data Link Disruption   SAE J1939   with engine control unit (MID128) 

Driving unit (MID144) in 5 seconds does not receive signals over the data channel   SAE J1939   from the engine control unit (MID128 ). Open or partial damage to the data channel wires between the blocks.

MID 144 PSID 202 FMI 9

Data Link Disruption   SAE J1939   with dashboard control unit ( MID140)

The vehicle control unit (MID144) does not receive date and time messages from the dashboard unit (MID140) . Data link is broken or one of the control units is faulty.   

MID 144 PSID 204 FMI 9

Data Link Disruption   SAE J1939   with braking control unit ( MID136)

Driving unit (MID144) during 5 seconds of not receiving signals over the data channel    SAE J1939   from the braking system control unit (MID136).   Broken or partial damage to data wire between the blocks.

MID 144 PSID 205 FMI 9

Data Link Disruption   SAE J1939   with gearbox control unit (MID130)

Driving unit (MID144) during 5 seconds of not receiving signals over the data channel    SAE J1939   from the gearbox control unit (MID130).   Broken or partial damage to data wire between the blocks.

MID 144 PSID 206 FMI 9

Data Link Disruption   SAE J1939   with retarder control unit ( MID222)

The vehicle control unit (MID144) does not receive signals through the data channel for 5 seconds    SAE J1939   from the retarder control unit (MID222 ). A break or partial damage to the data channel wires between the blocks.

MID 144 PSID 207 FMI 9

Data Link Disruption   SAE J1939   with gear selector control unit (MID223) 

Driving unit (MID144) during 5 seconds of not receiving signals over the data channel    SAE J1939   from the gear selector control unit (MID223).   Broken or partial damage to data wire between the blocks.

MID 144 PSID 208 FMI 9

Data Link Disruption   SAE J1939   with air suspension control unit ( MID150)

Driving unit (MID144) within 5 seconds to receive reports of the vehicle weight on the data channel    SAE J1939   from the air suspension control unit (MID150).  Broken or partial damage to data wire between the blocks.

MID 144 PSID 210 FMI 9

Data Link Disruption   SAE J1939   with outdoor lighting control unit ( MID216)

Driving unit (MID144) during 5 seconds is not receiving messages on the data channel    SAE J1939   from the outdoor lighting control unit (MID216).   Broken or partial damage to data wire between the blocks.

MID 144 PSID 211 FMI 9

Data Link Disruption   SAE J1939   with adaptive cruise control unit (MID219) 

Driving unit (MID144) during 5 seconds is not receiving messages on the data channel    SAE J1939   from the adaptive cruise control unit (MID219). Broken or partial damage to data wire  between the blocks.

MID 144 PSID 212 FMI 2

Data Link Disruption   SAE J1939   with tachograph control unit (MID220) 

The vehicle control unit (MID144) does not receive a message on the data channel for 5 seconds    SAE J1939   from the tachograph control unit (MID220 ). The break or partial damage to the data channel wires between the blocks.

MID 144 PSID 212 FMI 9

Data Link Disruption   SAE J1939   with tachograph control unit (MID220) 

The vehicle control unit (MID144) does not receive a message on the data channel for 5 seconds    SAE J1939   from the tachograph control unit (MID220 ). The break or partial damage to the data channel wires between the blocks.

MID 144 PSID 212 FMI 14

Data Link Disruption   SAE J1939   with tachograph control unit (MID220) 

The vehicle control unit (MID144) does not receive a message on the data channel for 5 seconds    SAE J1939   from the tachograph control unit (MID220 ). The break or partial damage to the data channel wires between the blocks.

MID 144 PSID 214 FMI 9

Data Link Disruption   SAE J1939   with additional equipment control unit ( MID249)

Driving unit (MID144) during 5 seconds is not receiving messages on the data channel    SAE J1939   from the control unit for additional equipment (MID249). Broken or partial damage to data wire  between the blocks.

MID 144 PSID 227 FMI 9

Data Link Disruption   SAE J1939   with air dryer control unit ( MID185)

Driving unit (MID144) during 5 seconds is not receiving messages on the data channel    SAE J1939   from the air dryer control unit (MID185).   Broken or partial damage to data wire between the blocks.

MID 144 PSID 230 FMI 4

Software failure

Incorrect software restart. Power outages, software malfunctions, or strong electromagnetic interference.

MID 144 PSID 230 FMI 5

Software failure

Incorrect interruption of the program due to a power failure. There was no power for at least 10 seconds when the ignition is on. Breakage or partial damage to the power cord or ground of the vehicle control unit .

MID 144 PSID 230 FMI 12

Software failure

Serious software malfunction and software restarted. Software error or strong electromagnetic interference. Reprogram the vehicle control unit first, if the fault persists, replace the vehicle control unit.

MID 144 PSID 232 FMI 2

Data feed   SAE J1939-2

The vehicle control unit does not communicate with the tachograph control unit over the data channel  SAE J1939.   Breakage of wires between the car control unit and the tachograph. A short to ground between the car control unit and the tachograph.