Brake Switch 'B' Circuit High
Indicates a high voltage condition in the brake switch B 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 system is seeing too much voltage in the switch circuit that tells the computer when you press the brake pedal.
What the computer is actually seeing
The brake control module expects the input from the switch to be low (around 0.1-0.5 volts when no brake applied) and high (around 4.5-5 volts when brake applied).
What a healthy reading looks like
Switch not pressed: 0.1-0.5V; Switch pressed: 4.5-5V.
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.
- 1Check for any blown fuses related to the brake system; replace as necessary. If fuses are good, proceed to step 2.
- 2Inspect the wiring and connectors for the brake switch 'B'. Look for damage, corrosion, or loose connections.
- 3Using a multimeter, measure the voltage at the brake switch 'B'. It should read between 0.1-0.5 volts when not pressed. If higher, replace the brake switch 'B'.
- 4If the switch is good, check the wiring harness for shorts to power or ground which could cause a high voltage signal.
- 5If all else checks out, suspect a faulty brake control module.
Common causes
- Faulty brake switch 'B'
- Shorted wiring in the brake switch circuit
- Corroded connectors
- Faulty brake control module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's best to fix this soon as brake system performance may be impacted.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, the code will return.
Why does it pair with other brake codes?
Related codes usually indicate issues with the brake system, often linked to the same components.
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