Diagnostic Trouble Code (DTC) Information PHM-000A

Condition 

The Phone module (PHM) checks the voltage supply to the spare microphone.

The diagnostic trouble code (DTC) is stored if the control module detects that:

• The voltage of the spare microphone is less than 0.025 V.

The control module's test for the diagnostic trouble code (DTC) starts in the event of:

• Ignition position 0, I and II.
• Battery voltage between 9 - 16 V.

Fig 1: Identifying Phone Module (PHM)

Courtesy of VOLVO CARS OF NORTH AMERICA.

Substitute Value 

• None.

Possible Source 

• The spare microphone has a short-circuit to ground or an open circuit.

Fault symptom[s] 

• Cellular phone/Other cellular phone problems
• Volvo On Call/Other Volvo On Call problems
• Text window and warning symbol/Text message