VOLVO
CEM-AFF4 - Tire pressurement sensor. 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 control module receives messages from a tyre pressure sensor, but the signal is too weak or cannot be interpreted correctly. It cannot identify which wheel is affected. Causes may be an internal fault in the sensor, a fault in the Remote Keyless Entry (RKE) receiver or low battery voltage in the sensor.
Possible causes
- Internal fault in the tyre pressure sensor
- Fault in the Remote Keyless Entry (RKE) receiver
- Low battery voltage in the tyre pressure sensor
What you can do
- 1Check the remote receiver's operation with the remote control, and troubleshoot it first if locking does not work
- 2If you have a diagnostic tool, read the frozen values for the fault code and check which sensor ID is stored
- 3Have a workshop replace the tyre pressure sensor whose ID matches the stored one
- 4Clear the fault code and road test to see whether it returns
Symptoms you may notice1
- A message appears in the information display
General guidance for car owners. Diagnosis on the car can point to a different cause.