VOLVO
CEM-C1A9611 - Brake Light Switch. General Electrical Failures. Circuit short to ground
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsV40 (2013–), V40 Cross Country (2013–)
Show models by year and engine (2)
What does this fault code mean?
Although the fault is named as a short circuit to ground, it applies when the brake light switch has jammed. The switch sits by the brake pedal, and when it does not respond to the pedal being pressed, the control module logs the fault. A jammed switch can keep the brake lights on all the time and affect cruise control and the start function.
Possible causes
- The brake light switch has jammed
- The brake light switch is damaged
- The brake light switch is incorrectly fitted
What you can do
- 1Check that nothing is under the brake pedal, such as a mat, and that the pedal moves freely
- 2Ask someone to check whether the brake lights go out when you release the brake. If they stay lit, the switch has probably jammed
- 3Check that the fuses for the brake lights and cruise control are intact, using the owner's manual
- 4With a diagnostic tool you can follow the brake switch position in live data and see whether it changes or stays still
- 5If the switch has jammed, is damaged or is incorrectly fitted, have a workshop correct or replace it
- 6Brake lights are important for road safety, so do not leave a fault that keeps them on for long; get it fixed promptly
Symptoms you may notice3
- The brake lights stay on all the time
- Cruise control will not engage or does not hold the set speed
- The engine does not start, or the start function does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.