Rear Brake Switch Circuit Fault
The rear brake switch circuit has an issue.
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)
When you press the brake pedal, a switch should send a signal to the computer. If there's a problem with that signal, your brake lights may not work, or the vehicle may not go into the right modes like cruise control.
What the computer is actually seeing
The vehicle's computer expects a voltage near 0 volts when the brake pedal is applied and close to the battery voltage (around 12-14 volts) when released. Any deviation from this can trigger the fault code.
What a healthy reading looks like
0 volts when brake applied, 12-14 volts when not 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.
- 1Check brake fluid level; low fluid can cause brake system alerts and codes.
- 2Inspect wiring and connectors at the brake switch for damage or corrosion. Repair as needed.
- 3Test the brake switch: when pressed, it should read close to 0 volts; when released, it should read battery voltage (12-14 volts). If faulty, replace the switch.
- 4Use a scan tool to clear the code and see if it reappears after testing the switch and wiring.
Common causes
- Faulty brake switch
- Wiring issues or shorts in the brake switch circuit
- Poor connector contact at the brake switch or main harness
- Faulty ABS control module (for some vehicles)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but if the brake lights are inoperative, it's unsafe as it may cause other drivers to be unaware when you're braking.
Will the code come back?
If the underlying issue isn't fixed, yes, the code will likely return after clearing it.
Why does this relate to the ABS system?
This code may impact ABS functionality since the ABS relies on brake switches to determine proper operation during braking.
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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