OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Chassis generic / SAE

C0205

Stop Lamp Switch Circuit

The ABS or stability control module has detected a fault in the stop lamp switch circuit. The brake light switch tells the module whether the driver is braking and is used to coordinate ABS, traction control and cruise control.

SystemChassis
Typegeneric / SAE
GroupC0
Range / number2 / 05

Possible causes

  • Stop lamp switch failed or misadjusted high
  • Wiring or connector fault medium
  • Blown stop lamp fuse low

Symptoms

  • ABS warning light on
  • ESC/stability control deactivated
  • Possible reduced brake assist
  • Speedometer may behave erratically

Inspection / repair

  • Difficulty: easy
  • DIY: possible
  • Estimated cost: 30–200 €
  • Estimated time: 0.3–1 h
  • Component: stop lamp switch
  • Component: abs control module
  • Component: cruise control module

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication