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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information PHM-0020

Condition




The diagnostic trouble code (DTC) is stored if the phone module (PHM) registers an open-circuit or a short-circuit to +12 V in the microphone signal to the handset.
The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on (not key position 3) and when the battery voltage is 9-16 V.

Substitute value
- Only hands-free operates.

Possible source
- Short-circuit to +12 V in the cable (microphone signal) between the handset and the control module
- Open-circuit in the cable (microphone signal) between the handset and the control module
- Contact resistance, oxidation or loose connections in the connectors.

Fault symptom[s]
- The carphone handset is not working.
- Message in the text display (applies only to phone modules (PHM) with Volvo On Call).