VOLVO
CPM-U300049 - Control Module. System Internal Failures. Internal electronic failure
System
Combustion Pre-heater Module (CPM)
Volvo models this fault code applies to
Applies to the following models:
9 modelsS60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The heater control module has found an internal electrical or software-related fault in its own circuits. The heater's function is blocked, and the heating can be poor or slow. The fault comes from the control module itself, for example a check error in the software.
Possible causes
- Checksum error in the software
- Damaged heater control module
- The software has been tampered with or changed in an unauthorised way
- Open circuit in the supply voltage or earth connection while the control module stores information
What you can do
- 1Erase the fault code and test start the heater. If the fault returns, it is a lasting fault.
- 2Check that the fuses for the heater are intact. Look in the car's manual to find where they are.
- 3If you have a diagnostic tool: start the heater after it has been off for a while and see whether the fault returns. Some faults only show at start-up.
- 4Have a workshop download the latest software to the heater and then check that the fault has cleared.
- 5If the fault remains after the software update, have a workshop replace the heater control module.
Symptoms you may notice4
- The parking heater does not work
- The heat does not get hot enough in the rear section
- The heat does not get hot enough in the front section
- The heater does not work with the temperature control
What the fault can affect1
- The heater's function is blocked
General guidance for car owners. Diagnosis on the car can point to a different cause.