VOLVO
CPM-3141 - Engine coolant temperature (ECT) sensor. Signal too high / Signal missing
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?
Although the code name refers to a signal that is too high or a missing signal, the fault concerns the signal from the coolant temperature sensor, which is too low. The heater cannot be activated until the code has been cleared. The cause may be a break in the cable or a damaged sensor.
Possible causes
- Break in the wire between the CPM and the coolant temperature (ECT) sensor
- Damaged engine coolant temperature (ECT) sensor
What you can do
- 1Clear the code and switch the ignition on; if the code returns, the fault is still present
- 2If you have a diagnostic tool, read the coolant temperature and compare it with the engine temperature; they should be roughly equal
- 3Check that the connectors at the preheater module and at the sensor are secure and free from oxidation
- 4Use a multimeter to check that the cable between the connectors is intact; a break means the cable must be repaired or replaced
- 5If the fault returns, have a workshop measure the sensor resistance and replace the sensor if needed
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.