Brake Switch Circuit Malfunction
The brake switch is not functioning correctly in the system.
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 press the brake pedal. If it fails, the computer doesn’t know the brake is being applied, which can affect features like cruise control or transmission behavior.
What the computer is actually seeing
The computer monitors voltage signals from the brake switch. When the pedal is pressed, voltage should change from 0 volts (off) to around 5 volts (on).
What a healthy reading looks like
Expected voltage when brake pedal is pressed: 4.5V - 5.0V; when off: 0V - 0.2V.
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.
- 11. Inspect the wiring and connectors at the brake switch for damage or corrosion. If any issues are found, repair or replace as necessary.
- 22. Use a multimeter to measure the voltage at the brake switch connector. With the brake pedal not pressed, voltage should be near 0V.
- 33. Press the brake pedal and check if the voltage changes to between 4.5V and 5.0V. If it does not, replace the brake switch.
- 44. If voltage readings are correct, check the brake switch signal at the control module. If the module does not receive the correct signal, consider possible issues with the module itself.
Common causes
- Faulty brake switch
- Wiring issues or damaged connectors
- Software glitch in the control module
- Corrosion in the electrical connectors
Typical repair cost
$$ - $$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
While you can drive the vehicle, features like cruise control may not work, and the vehicle may not behave as expected.
Will this code come back after clearing it?
If the underlying issue is not fixed, the code is likely to return.
Why does this code appear with other codes?
It often pairs with codes related to brake controls, indicating systemic issues with braking system inputs.
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