VOLVO
ECM-931F - Clutch pedal switch B. Signal missing
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?
Although the code is titled signal missing, it is set when clutch pedal switch B stays activated for a long time while driving with a gear engaged. The switch detects when the clutch pedal is pressed to its lower position, and it tells the system whether the pedal is pressed or released for automatic engine start/stop.
Possible causes
- Loose connection or oxidation in the connector
- Short circuit or open circuit in the connections to the sensor
- Damaged clutch pedal switch B
What you can do
- 1Check that the fuses are intact. Their locations are in the handbook or on the fuse box cover
- 2Test the cruise control and automatic start/stop with the controls, or on a test drive, so you can see how the fault shows
- 3Check the connector at clutch pedal switch B: is it secure, and is there play or oxidation in the connector
- 4Use a multimeter to check that the wiring to the clutch pedal switch has no open circuit and no short to ground or plus
- 5If you have a diagnostic tool: read clutch pedal switch B in live data while the clutch is pressed and released. The value should change when the pedal moves
Symptoms you may notice4
- Driving with automatic engine start/stop does not work
- Idling with automatic engine start/stop does not work
- Starting with autostart does not work
- Cruise control does not disengage
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.