VOLVO
PHM-000A - Emergency microphone Signal too low/Signal missing
System
Phone Module (PHM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
6 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013), XC90 (2003–)
What does this fault code mean?
The phone module (PHM) monitors the power supply to the spare microphone. The fault covers a signal that is too low or missing from the spare microphone, which can be caused by a short circuit to ground or an open circuit.
Possible causes
- The spare microphone is short-circuited to ground
- The spare microphone has an open circuit
What you can do
- 1Check the fuses; see the owner's manual for where they are
- 2Test the phone and Volvo On Call with the buttons or in a road test to see how the fault shows
- 3Use a multimeter to check that the spare microphone wiring is not broken, chafed or shorted to ground
- 4If the fault remains, have a workshop fault-trace the spare microphone
Symptoms you may notice3
- Mobile phone function problems
- Volvo On Call function problems
- Text message in the display together with a warning symbol
General guidance for car owners. Diagnosis on the car can point to a different cause.