VOLVO
CPM-0318 - Fuel pump. Signal 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 registered that the signal on the heater fuel pump cable is too high. The cause may be a short circuit to supply voltage in the cable or a damaged fuel pump. The heater cannot be started until the code has been cleared.
Possible causes
- Live-voltage short in the wire running from the CPM to the fuel pump
- Damaged fuel pump
What you can do
- 1Clear the code and start the heater again; if the code returns, the fault is still present
- 2If you have a diagnostic tool, activate the fuel pump and listen for a ticking sound; if it does not start, the fault is probably permanent
- 3Disconnect the connector at the fuel pump and check that the contacts are tight and free from oxidation
- 4Use a multimeter to check that the fuel pump cable carries no voltage when the heater is off; if it does, the cable is shorted to positive
- 5If the fault returns, have a workshop check the fuel pump and the wiring to the preheater module
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.