VOLVO
SUB-0021 - Control module. Internal fault
System
Subwoofer Module (SUB)
Volvo models this fault code applies to
Applies to the following models:
1 modelC70 (2006–2013)
Show models by year and engine (1)
What does this fault code mean?
The subwoofer module has registered an internal fault, which means no sound comes from the subwoofer. The fault lies in the module itself, so a permanent fault requires replacement.
Possible causes
- Internal fault in the subwoofer module
What you can do
- 1Erase the code with a diagnostic tool and see whether it returns
- 2Check that the connectors to the subwoofer are secure and free from corrosion
- 3If the fault remains, have a workshop replace the subwoofer module
- 4After replacement, check that sound is heard from the subwoofer again
Symptoms you may notice1
- No sound from the subwoofer
General guidance for car owners. Diagnosis on the car can point to a different cause.