Brake Switch Circuit Malfunction
The brake switch is not functioning correctly.
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 car when you're pressing the brake pedal. If it's malfunctioning, the computer doesn't know if you're braking or not, which can cause issues with features like cruise control or anti-lock brakes.
What the computer is actually seeing
The computer expects a voltage change from the brake switch, typically between 0V when not pressed to around 5V when pressed. If it stays high or low without change, a fault is flagged.
What a healthy reading looks like
Brake switch voltage should be 0-0.5V when not pressed, and 4.5-5V 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.
- 1Inspect wiring and connectors at the brake switch for damage or corrosion. Decision Point: If damaged, repair or replace and retest. If not damaged, proceed to next step.
- 2Check the voltage at the brake switch. You should see 0-0.5V when the pedal is not pressed and 4.5-5V when pressed. Decision Point: If voltage readings are outside expected values, replace the brake switch. If readings are correct, continue to next step.
- 3Verify proper operation of the brake pedal linkage to the switch. Decision Point: If the linkage is misaligned or binding, adjust it. If everything checks out, consider potential PCM issues.
Common causes
- Faulty brake switch
- Wiring damage or corrosion
- Connector issues at the brake switch
- Brake pedal alignment problem
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderately severe, so it's best to fix it soon to maintain safety features like ABS and cruise control.
Will this code come back?
If the underlying issue isn't fixed, yes, it can return after clearing.
Why does this code sometimes pair with other codes?
Issues with the brake switch can affect multiple systems, leading to various related fault codes.
Working a real vehicle right now?
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