Source: https://truckmanualshub.com/mid150-ecs-volvo-air-suspension-control-unit-fault-codes/
Timestamp: 2019-04-25 08:34:41+00:00

Document:
FMI 12 Restarting the system due to an internal software failure.
FMI 5 Broken wire power or ground. The solenoid valve may be faulty.
FMI 6 Strong current or short to ground. Short to power lead to ground wire or defective solenoid valve.
FMI 7 Mechanical failure of the solenoid valve. Valve components jammed in open or closed position. Before replacing the valve, check for air leaks and verify that the air pressure sensor reads in the air springs of the front axle.
FMI 5 Break of a wire of food, management. Shorting control wire to ground. The solenoid valve may be faulty.
FMI 6 Control wire short to positive or defective solenoid valve.
FMI 2 Damaged level sensor, short circuit of the signal wire to the power wire or break in the ground wire is damaged. Possible level sensor malfunction.
FMI 3 The signal voltage at the ECS unit’s contact from the level sensor exceeds 4.5 V. Closure of the signal wire to the power supply wire. Breakage of the ground wire. Possible level sensor malfunction.
FMI 4 The signal voltage at the ECS unit contact from the level sensor is less than 0.5 V. Shorting of the signal wire to ground. Broken power or signal wire. Possible level sensor malfunction.
FMI 7 Damaged level sensor, short circuit of the signal wire to the power wire or break in the ground wire is damaged. Possible level sensor malfunction.
FMI 2 Broken wire mass sensor. Shorting the signal wire to the power supply wire. Probably faulty sensor.
FMI 3 The signal voltage at the ECS unit contact from the pressure sensor exceeds 4.5 V. Closure of the signal wire to the power supply wire. Breakage of the ground wire. Possible pressure sensor malfunction.
FMI 4 The signal voltage at the ECS unit contact from the pressure sensor is less than 0.5 V. Shorting of the signal wire to ground. Broken signal wire or sensor power wire. Possible pressure sensor failure.
FMI 7 Water freezing or partial contamination in mains or other air suspension components. Shorting the signal wire to power supply or a broken ground wire.
FMI 3 The signal voltage at the ECS unit contact from the pressure sensor exceeds 4.5 V. Closure of the signal wire to the power supply wire. Break wire mass. Possible pressure sensor malfunction.
FMI 3 Shorting the signal wire to the power supply. A broken ground or defective load sensor.
FMI 4 Shorting the signal wire to ground. Break signal or power wires. The sensor may be faulty.
FMI 3 The signal voltage at the ECS unit contact from the pressure sensor exceeds 4.5 V. Closure of the signal wire to the power supply wire . Breakage of the ground wire. Possible pressure sensor malfunction.
FMI 7 The ECS unit registers that one of the switches on the air suspension control panel is in two positions simultaneously. A short to ground between the console and the ECS unit. The air suspension control panel may be faulty.
FMI 7 Mechanical fault relay.
FMI 2 Malfunction in the wiring or data channel connectors between the ECS unit and other control units.
FMI 13 Programming error or internal malfunction of the air suspension control unit. Reprogramming, in the event of a recurring DTC, replace the control unit.
FMI 2 Malfunction in the wiring or data channel connectors between the ECS unit and other control units. Probably faulty control unit.
FMI 0, 1, 2, 13, 14 Incorrectly programmed parameters. Check the correctness of the parameters set. Reprogram the ECS unit.
FMI 3 Supply voltage of level sensors is higher than 5.5 V. Short circuit of the sensor power supply wire to a higher voltage.
FMI 4 The power supply voltage level sensors below 4.5 V. Closure of the power wire to ground.
FMI 3 The supply voltage of the pressure sensors is higher than 5.5 V. Closure of the sensor power supply wire to a higher voltage.
FMI 4 The supply voltage of the pressure sensors is below 3.5 V. Shorting of the power wire to ground.
FMI 14 The supply voltage of the pressure sensors is higher than 16 V. Closure of the power supply of the sensors to a higher voltage.
FMI 7 The air suspension control unit registers that the switch is in two positions simultaneously. Short circuit between the ECS unit and the switch or the switch is faulty. Also check the fuses and relays.
FMI 2 Shorting the signal wire to ground, broken ground wire, or the sensor is faulty.
FMI 3 The voltage of the sensor signal wire exceeds 4.5 V. Shorting of the signal wire to the power wire, a break in the ground wire or a sensor is faulty.
FMI 4 Closing the signal wire to ground. Broken power or signal wire. The sensor may be faulty.
FMI 7 Low pressure measured by the sensor. The air lines are clogged, the signal wire is shorted to electrical power, a ground wire is broken, or the sensor is faulty.
FMI 13 Load pointer not calibrated or not calibrated correctly.
FMI 14 Load indicator not calibrated correctly.
FMI 5 Broken power wire, ground, or valve is faulty.
FMI 6 Short to ground or faulty valve.
FMI 7 The solenoid valve does not fill or empty the air springs, and the air pressure sensor in the air springs does not register any changes. Seizure of internal valve components, severe air leakage, or defective air pressure sensor.
FMI 5 Broken power wire, ground, or valve malfunctioning.
FMI 7 Solenoid valve does not fill or empty the air springs, and the air pressure sensor in the air springs does not register any changes. Seizure of internal valve components, severe air leakage, or defective air pressure sensor.
FMI 2 Shorting the signal wire to the power supply, a broken ground wire, or a sensor is faulty.
FMI 3 The signal voltage from the pressure sensor exceeds 4.5 V. Closing the signal wire to the power supply, a ground wire is broken, or the sensor is faulty.
FMI 4 The signal voltage from the pressure sensor is below 0.5 V. Shorting of the signal wire to ground, break in the signal wire, break in the power wire, or sensor is faulty.
FMI 7 Low pressure measured by sensor. Low pressure measured by the sensor. The air lines are clogged, the signal wire is shorted to electrical power, a ground wire is broken, or the sensor is faulty. The solenoid valve may be faulty.
FMI 7 The air suspension control unit registers that the switch is in two positions simultaneously. Short circuit between the ECS unit and the switch or the switch is faulty.
FMI 13 Incorrect sensor calibration or sensor has never been calibrated. Perform calibration.
FMI 2 Damaged level sensor thrust. Shorting the signal wire to the power supply, a broken ground wire, or a sensor is faulty.
FMI 3 The signal voltage from the height sensor exceeds 4.5 V. Shorting of the signal wire to the power supply, break in the ground wire, or the sensor is faulty.
FMI 4 The signal voltage from the level sensor is below 0.5 V. Shorting of the signal wire to ground, break in the power wire, break in the signal wire, or the sensor is faulty.
FMI 7 The height value displayed by the sensor is too small. Damaged level sensor, short circuit of the signal wire to the power supply, break in the ground wire, or the sensor is faulty.
FMI 9 The air suspension control unit MID150 does not receive signals from the engine control unit MID128 via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The air suspension control unit MID150 does not receive signals from the vehicle control unit MID144 via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The MID150 air suspension control unit does not receive signals from the MID140 dashboard control unit via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The air suspension control unit MID150 does not receive signals from the retarder control unit MID222 via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The air suspension control unit MID150 does not receive signals from the MID216 outdoor lighting control unit via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The air suspension control unit MID150 does not receive signals from the additional rear axle control unit MID184 via the SAE J1939 data channel. Breakage or partial damage to the wires of the data channel between the blocks.
FMI 9 The air suspension control unit MID150 does not receive signals from the air dryer control unit MID185 via data channel SAE J1939. Breakage or partial damage to the wires of the data channel between the blocks.

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