VOLVO
PHM-7B11 - Handset supply Signal too low
System
Phone Module (PHM)
Volvo models this fault code applies to
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?
Although the code is named signal too low for the handset supply, it applies to the supply wire to the handset being short-circuited to ground. The handset then does not work for individual calls, and only hands-free works.
Possible causes
- The supply wire to the handset from the carphone control module (PHM) is short-circuited to ground
What you can do
- 1Read and note the code before clearing it, so the workshop can see it
- 2Check that the handset connector is firmly seated and free from corrosion
- 3Use a multimeter to check that the supply wire to the handset has no contact with ground (the body), once the connector is checked
Symptoms you may notice3
- The handset does not work for individual calls
- The other party cannot be heard or cannot hear through the handset
- A text message appears together with a warning symbol
What the fault can affect1
- Only hands-free operates
General guidance for car owners. Diagnosis on the car can point to a different cause.