VOLVO
CPM-3601 - Control module. Supply voltage too high
System
Combustion Pre-heater Module (CPM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The CPM has logged a supply voltage that stayed too high for some time, and this sets the code. The cause may be a damaged generator, or a battery charger or starter unit with an excessive charging voltage connected to the car. The heater cannot be activated until the code has been cleared.
Possible causes
- Damaged generator (GEN)
- Battery charger or starter unit with incorrect charging voltage is connected
What you can do
- 1Check whether an external battery charger or starter unit is connected to the car; if so, disconnect it and clear the code
- 2If you have a diagnostic tool, read battery voltage with the engine running and see whether it stays steady; a voltage that is too high points to a charging fault
- 3Replace the fuse feeding the CPM with a new one; a partly blown fuse can cause intermittent faults
- 4Use a multimeter to check battery voltage at the CPM supply; an abnormal reading means a workshop should look further
- 5If the fault returns, have a workshop check the generator and the charging system
Symptoms you may notice2
- Poor heating in the passenger compartment
- The parking heater does not work
What the fault can affect1
- The heater cannot be activated until the fault code has been cleared
General guidance for car owners. Diagnosis on the car can point to a different cause.