Brake Switch Circuit Fault
There’s a fault in the brake switch circuit.
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 vehicle's computer when you press the brake pedal. If it's not working, the computer may not know you're braking, affecting systems like cruise control and possibly causing brake lights to stay on or off.
What the computer is actually seeing
The computer expects a certain voltage (typically around 0V with brake off and around 5V with brake pressed) from the brake switch. If it sees an open circuit or a voltage that doesn't match these expectations, it triggers this code.
What a healthy reading looks like
Brake switch should show 0V when brake is off and approximately 5V when brake is 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.
- 1Check brake fluid level; low fluid can affect switch operation. Is it okay? Yes: Proceed to next step; No: Refill fluid and test again.
- 2Inspect wiring and connectors at the brake switch for damage or corrosion. Are they okay? Yes: Proceed to next step; No: Repair or replace damaged wiring/connectors and test again.
- 3Use a multimeter to check the voltage at the brake switch connector. Is it close to 0V with the brake off and ~5V with the brake pressed? Yes: Test the brake switch; replace if faulty; No: Inspect the circuit between the switch and the ECU for open/shorts.
Common causes
- Faulty brake switch
- Wiring issues or shorts in the circuit
- Corroded or loose connectors
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally drivable, but you may lose cruise control and brake light functionality.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, the code will likely return.
Why does this code pair with other codes?
Brake switch faults can affect multiple systems, often triggering related codes.
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