VOLVO
CEM-4F32 - Battery temperature. 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 central electronic module (CEM) monitors the signal from the battery temperature sensor and has registered a signal that does not match. The sensor tells the system how warm the battery is, and when the reading is implausible the code is set. The fault may be permanent, or it may have occurred before and not be active right now.
Possible causes
- Damaged battery temperature sensor
- Poor contact or open circuit in the sensor signal or ground wire
- Signal wire shorted to supply voltage
What you can do
- 1Check that the battery is in good condition and that its terminals are tight
- 2Check that the sensor connector is fully engaged and free from oxidation
- 3Check the signal and ground wires for open circuits and chafing, especially where they are exposed to heat or movement
- 4Read the sensor value with diagnostic equipment; replace the sensor if it gives an implausible reading and the wiring is intact
Symptoms you may notice2
- The battery discharges
- The fault usually gives no other clear symptoms
General guidance for car owners. Diagnosis on the car can point to a different cause.