VOLVO
CEM-4F4A - Seat belt buckle, rear left-hand. Faulty signal
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsC30 (2007–2013), C30 Electric (2011–2013), C70 (2006–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The CEM monitors the left rear belt buckle. If the signal level is faulty, the code is set. The information lamp may light and a message may appear in the display. The fault may lie in the signal wire or in the buckle.
Possible causes
- A damaged signal wire between the rear left buckle and the CEM
- A faulty seat belt buckle
What you can do
- 1Safety: the seat belt system is part of the crash protection. Do not work on the wiring or the buckle yourself. Have a workshop check it
- 2Look for chafed or pinched cables at the rear left seat belt, without removing anything
- 3Latch and unlatch the belt several times and see whether the information lamp changes. If it does not, the fault is probably permanent
- 4After the work, clear the code and check that the information lamp goes out
Symptoms you may notice2
- The information lamp is lit
- A message appears in the display
General guidance for car owners. Diagnosis on the car can point to a different cause.