VOLVO
CEM-8F28 - Windshield wiper, high speed relay. Signal missing. Intermittent fault
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
This fault code has different meanings depending on model, model year or engine. Select the meaning that applies to your car.
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The fault is intermittent: the CEM registered a break at the relay for the high wiper speed on an earlier occasion, but the break is no longer present. The wipers may then run only at the lowest speed.
Possible causes
- Open circuit in the signal wire
- Open circuit in the power supply to the relay
- Faulty relay
- Relay not fitted
What you can do
- 1Clear the code and check whether it returns; an intermittent fault can be a temporary disturbance
- 2Check that the relay for the high wiper speed is securely connected and not loose
- 3Check the connectors for contact resistance, oxidation and play
- 4Look for a break in the wire between the CEM and the relay, especially where it may have chafed or come loose
- 5If the fault returns, have a workshop check the relay and the wiring
Symptoms you may notice1
- The wipers only work at the lowest speed
General guidance for car owners. Diagnosis on the car can point to a different cause.