VOLVO
CEM-P157172 - Brake Switch. Mechanical Failures. Actuator stuck open
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The CEM checks the brake lamp diagnostic switch (BDS) at the brake pedal. If the switch does not respond although the brake pedal is pressed hard enough, it is stuck open. The fault affects cruise control and autostart, because the CEM uses the signal from the brake pedal.
Possible causes
- The brake switch (BDS) is installed incorrectly
- The brake switch (BDS) is damaged
- The brake switch (BDS) is stuck
What you can do
- 1Check that the brake lights come on when you press the pedal and go off when you release it. This shows whether the switch works in practice
- 2Check that the brake switch is correctly fitted at the pedal and is not stuck
- 3Check that the pedal arm moves freely and is not stiff
- 4Check the brake light fuse in the engine bay or fuse box. If it has blown, check its circuit for a short to earth before replacing it
- 5With a diagnostic tool, clear the fault code and run the test again. If the code returns straight away, the fault is active
- 6The brake switch affects the brake lights and cruise control. Have a workshop repair the fault, and drive carefully until it is done
Symptoms you may notice4
- Autostart does not work
- Cruise control cannot be engaged
- Cruise control does not hold the set speed and disengages
- Cruise control does not disengage properly
General guidance for car owners. Diagnosis on the car can point to a different cause.