Brake Switch Circuit Fault
There's a problem with the brake switch circuit signal.
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 tells the computer when you press the brakes. If it's not sending the correct signals, the system can't respond properly.
What the computer is actually seeing
When pressing the brake pedal, the system expects a voltage change at the brake switch circuit. A faulty switch may send a constant voltage (like 0V or 12V) when it should vary between them depending on whether the pedal is pressed or not.
What a healthy reading looks like
Brake switch should show around 0V when the brake pedal is not pressed and around 12V when pressed.
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 brake switch wiring and connectors for damage or corrosion.
- 22. Check brake fluid level—low fluid can affect brake switch operation.
- 33. Measure voltage at the brake switch connector: expect 0V (not pressed) and ~12V (pressed). If readings are off, proceed to the next step.
- 44. Swap the brake switch with a known good one if available.
- 55. If the problem persists, check the wiring for continuity and shorts to ground or power.
Common causes
- Faulty brake switch
- Wiring issues in the brake switch circuit
- Bad connector at the brake switch
- Short circuit or open circuit in the wiring
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive with this code?
It may still drive, but brake-related systems might be affected. Fix it soon.
Will the problem come back after clearing the code?
If the underlying issue isn't fixed, yes, the code will likely return.
Why might this code appear with other codes?
Multiple faults can occur in related systems; the brake system is interconnected with safety sensors.
Working a real vehicle right now?
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