VOLVO
CPM-0402 - Fuel pump. Signal too low
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 registered that the signal from the heater fuel pump is too low, and the heater switches off when the code is set. The cause may be a short circuit to earth in the cable or a damaged fuel pump.
Possible causes
- Short circuit to earth in the cable between the CPM and the fuel pump
- Damaged fuel pump
What you can do
- 1With a diagnostic tool, activate the fuel pump: no ticking sound means a probably permanent fault, while a pump that starts points to an intermittent one
- 2Disconnect the connector at the fuel pump and check the contacts for oxidation, looseness and poor connections
- 3Use a multimeter to check that the cable has no contact with earth (the body); if it does, the cable is shorted
- 4Clear the code and check that the heater starts after the repair
- 5If the fault returns, have a workshop check the fuel pump and the cable to the preheater module
Symptoms you may notice2
- Poor heating in the passenger compartment
- The parking heater does not work
What the fault can affect2
- The heater switches off when the code is set
- If the heater is started again, it makes a new start attempt
General guidance for car owners. Diagnosis on the car can point to a different cause.