Brake Switch Fault
The brake switch circuit 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 computer when you're pressing the brake. If it fails, the system thinks you're always pressing or never pressing the brake, which can affect safety systems like ABS.
What the computer is actually seeing
The brake switch sends a signal to the computer when the brake pedal is pressed. A normally functioning switch should show a voltage change from 0V (when not pressed) to 5V (when pressed).
What a healthy reading looks like
When the brake pedal is not pressed, expect about 0.5V to 1V. When pressed, it should jump close to 5V.
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.
- 1Step 1: Check the brake fluid level. Make sure it is at the correct level.
- 2Step 2: Inspect the brake switch for physical damage or misalignment. Ensure it engages properly when the brake pedal is pressed.
- 3Step 3: Test the brake switch using a multimeter. When the brake pedal is pressed, voltage should change from about 1V to around 5V. If no change, replace the switch.
- 4Step 4: Check the wiring and connectors leading to the brake switch. Look for frays, breaks, or corrosion.
- 5Step 5: If all above tests are normal, examine the ABS module for faults or failures.
Common causes
- Faulty brake switch
- Wiring issues
- Corrosion in connectors
- Faulty ABS module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not recommended since brake-related faults can impact stopping power and ABS operation.
Will this code come back after clearing?
If the underlying issue isn't fixed, the code is likely to return after clearing.
Why does this code sometimes pair with other ABS codes?
Brake switch faults can affect multiple ABS functions, triggering related codes.
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