VOLVO
CEM-C1A9609 - Brake Light Switch. General Failure Information. Component Failures
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?
The brake light switch sits by the brake pedal and should register when the pedal is pressed. The control module checks the switch, and the fault is logged when the switch does not respond even though brake pressure is present, on several brake applications during the same drive. The fault may be caused by a switch that is incorrectly fitted, damaged or jammed.
Possible causes
- The brake light switch is incorrectly fitted
- The brake light switch is damaged
- The brake light switch has jammed
What you can do
- 1Ask someone to watch the rear lights while you press the brake. If the brake lights do not come on, or stay on all the time, this matches the fault
- 2Check that the brake pedal moves freely and that the switch at the pedal is secure and undamaged
- 3Check the fuses for the brake lights and cruise control in the fuse box, using the owner's manual
- 4If you have a diagnostic tool, look at the brake switch position in live data and check that it changes when you press and release the brake
- 5If the switch is incorrectly fitted, damaged or jammed, have a workshop correct or replace it
- 6Brake lights matter to other road users, so a fault that stops them coming on under braking should be fixed promptly
Symptoms you may notice4
- The brake lights stay on all the time or do not work
- Cruise control will not engage, does not hold the set speed or cuts out
- The engine does not start, or the start function does not work
- Text message and warning symbol in the display
General guidance for car owners. Diagnosis on the car can point to a different cause.