What does fault code CEM-101B mean?

Diagnostic fault code details for CEM-101B (Volvo C30 (2007–2013), Volvo C30 Electric (2011–2013), Volvo C70 (2006–2013)). Repair service at OBD Tuning.

VOLVO

CEM-101B - Control module, memory fault. 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?

The CEM has logged an internal memory fault within the unit itself. The fault may be intermittent, meaning it was present at an earlier time but is no longer there, or permanent, meaning it remains and must be fixed. The instruments, turn signals and lighting may then be affected.

Possible causes

Internal fault in the control module

What you can do

1Clear the code and restart the car
2If you have a diagnostic tool, read the code after the restart; if it does not return, the fault is probably intermittent
3Check that the battery is charged and that the battery terminals are clean and tight
4Check that the fuses for the CEM are intact
5If the fault is permanent and returns, have a workshop replace the CEM

Symptoms you may notice4

No gauges are working
The instrument lighting does not operate
The turn signal lamps do not operate
Poor performance

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