VOLVO
CPM-U300016 - Control Module. General Electrical Failures. Circuit voltage below threshold
System
Combustion Pre-heater Module (CPM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The heater control module has measured a supply voltage that is too low compared with the voltage the central electronic module receives. The heater's function is blocked, and the heating in the cabin can be poor. The cause may be a weak supply from the battery or poor contact, but a damaged charging system can also cause the fault.
Possible causes
- Contact resistance and oxidation in the connections
- Poorly charged battery or corroded connecting cables
- Damaged battery
- Damaged charging system
What you can do
- 1Check that the fuses for the heater are intact. Look in the car's manual to find where they are.
- 2With the engine off, measure the battery voltage with a multimeter. A weak voltage points to a poor battery.
- 3Look for corrosion and loose cable clamps and connectors at the battery and at the heater. Clean or tighten them.
- 4If you have a diagnostic tool: read the voltage in live data for the heater and compare it with the battery voltage.
- 5If the battery is damaged or the charging system does not charge correctly, have a workshop check the charging system.
Symptoms you may notice2
- Poor heating in the cabin
- The parking heater does not work
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.