What does fault code CEM-8A03 mean?

Diagnostic fault code details for CEM-8A03 (Volvo C30 (2007–2013), Volvo C30 Electric (2011–2013), Volvo C70 (2006–2013)). Repair service at OBD Tuning.

VOLVO

CEM-8A03 - Relay, high beam. Internal fault

System

Central Electronic Module (CEM)

Volvo models this fault code applies to

Applies to the following models:

5 models

C30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)

Show models by year and engine (5)

What does this fault code mean?

CEM has registered an internal fault, and the fault code is set when the main beam relay is not activated. The high beam then does not work as it should.

Possible causes

Internal fault in the control unit

What you can do

1Switch the ignition off, then on again, and check whether the high beam works normally
2Clear the fault code and test-run the car to see whether it returns
3If it was a one-off disturbance at start-up, no further action is needed
4If the fault returns often or is permanent, a workshop should replace the CEM

Symptoms you may notice1

High beam does not work

General guidance for car owners. Diagnosis on the car can point to a different cause.