Brake Switch Failure
The brake switch is not functioning as expected.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The brake switch signals when you press the brake pedal. If it fails, your vehicle may not recognize you’re trying to stop, which is a safety issue.
What the computer is actually seeing
The vehicle’s computer sees an unexpected voltage or no signal from the brake switch. Normally, it should see 0 volts (off) when the pedal isn't pressed and around 12 volts (on) when it is pressed.
What a healthy reading looks like
0 volts when the brake is not applied, 12 volts when applied.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the brake switch for physical damage or wear. If it's damaged, replace it.
- 22. Check the wiring and connector at the brake switch for continuity and corrosion. Repair as needed.
- 33. Use a multimeter to test for expected voltage at the brake switch connector with the pedal pressed and released; confirm it's 12 volts (on) and 0 volts (off).
- 44. If the voltage is incorrect, replace the brake switch. If voltage is correct, check the vehicle's computer for faults.
Common causes
- Faulty brake light switch
- Wiring issue or corroded connectors
- Faulty brake pedal assembly
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Driving with a faulty brake switch can be hazardous since your brake lights may not function, affecting other drivers' awareness.
Will this code come back after clearing?
If the underlying issue isn't addressed, yes, the code is likely to return.
Why might this code appear alongside others?
Multiple codes can indicate interconnected systems, like brake and stability control, reacting to the same brake function failure.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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