Source: https://truckmanualshub.com/mid231-volvo-fh-mobile-phone-controls-fault-codes/
Timestamp: 2019-04-25 07:46:09+00:00

Document:
FMI 12 Crash in software. Turn off and turn on the phone. Try to disconnect the car’s power from the batteries for a while.
FMI 2 The supply voltage on the phone control unit is above 48 V. A violation in the power system or a generator is faulty.
FMI 12 Faulty processor in the telephone control unit. Try to disconnect the car’s power from the batteries for a while. If the fault persists, replace the control unit with a mobile phone.
FMI 3 The voltage on the contacts of the phone control unit from the speaker is higher than 3.6 V. Short circuit of wires between the phone control unit and the speaker to ground. Breakage of wires in the speaker circuit. The speaker may be faulty.
FMI 4 The voltage on the contacts of the phone control unit from the speaker is below 1.4 V. Short circuit of wires between the phone control unit and the speaker to a higher voltage. Possible closure inside the speaker.
FMI 4 The voltage at the contacts of the phone control unit from the microphone is below 4 V. Shorting of wires between the phone control unit and the microphone to ground. Broken wire in the microphone circuit. The microphone may be defective.
FMI 5 The voltage on the contacts of the phone control unit from the microphone is above 4.8 V. Short circuit of wires between the phone control unit and the microphone to a higher voltage. Broken wire in the microphone circuit. Possible breakage inside the microphone.
FMI 5 The voltage at the contacts of the telephone control unit from the switch is below 3.3-4.1 V. There is a break in the wiring between the switch and the telephone control unit.
FMI 3 The voltage on the contacts of the telephone control unit from the microphone in the handset is higher than 4.5 V. Short circuit of the wires between the control unit of the telephone and the microphone in the handset is at a higher voltage.
FMI 4 The voltage on the contacts of the phone control unit from the microphone is below 2 V. Shorting of wires between the phone control unit and the microphone to ground. Broken wire in the microphone circuit. The microphone may be defective.
FMI 3 The voltage on the contacts of the telephone control unit from the speaker in the tube is higher than 4.5 V. Short circuit of wires between the control unit of the telephone and the speaker in the tube to a higher voltage.
FMI 4 The voltage on the contacts of the phone control unit from the speaker is below 0.5 V. Short circuit of wires between the phone control unit and the speaker to ground. Breakage of wires in the speaker circuit. The speaker may be faulty.
FMI 3 The power supply voltage of the handset is higher than 13.2 V. Short circuit of the wiring between the handset and the telephone control unit to ground. Breakage or partial damage to the wires between the handset and the telephone control unit.
FMI 4 The power supply voltage of the handset is below 10.8 V. Short circuit between the handset and the telephone control unit to ground. Breakage or partial damage to the wires between the handset and the telephone control unit.

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