VOLVO
ECM-CD0A - Battery Monitoring Sensor (BMS). Incorrect hardware
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The battery monitoring sensor (BMS) has registered a hardware fault. The sensor monitors the battery's condition, and the engine control module uses that information to regulate alternator charging. The fault switches off the automatic start/stop function.
Possible causes
- Damaged battery monitoring sensor (BMS)
What you can do
- 1Check that the fuses are intact. Their locations are in the owner's manual
- 2Check that the battery is charged and that the battery terminals are tight
- 3If you have a diagnostic tool: read the battery voltage in live data and check that it follows the vehicle's other voltage readings
- 4Check the connector at the battery monitoring sensor for loose contacts and corrosion
- 5Erase the fault code and road test the car with automatic start/stop to see whether it returns
- 6If the fault returns, have a workshop replace the battery monitoring sensor
Symptoms you may notice1
- Automatic engine start/stop does not work, both while driving and at idle
What the fault can affect1
- The automatic engine start/stop function is switched off
General guidance for car owners. Diagnosis on the car can point to a different cause.