Brake Sensor Signal Fault
Indicates a fault in the brake sensor signal 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 system detects that the brake sensor, which tells the computer when the brakes are being applied, is malfunctioning due to wiring issues or a bad sensor.
What the computer is actually seeing
The brake sensor signal voltage is either too high or too low. The normal operating voltage should be close to 0 volts when not engaged and around 5 volts when the brakes are applied.
What a healthy reading looks like
Idle brake signal voltage: 0-0.5V, Engaged brake signal voltage: 4.5-5V through the sensor.
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 the brake fluid level. Ensure it's at the correct level.
- 2Inspect the wiring harness and connectors for damage or corrosion.
- 3Test the brake sensor output voltage, it should be 4.5-5V engaged, and 0-0.5V not engaged.
- 4If voltage readings are incorrect, replace the brake sensor and recheck the system.
- 5If the sensor is fine, trace the wiring back to the computer for shorts or open circuits.
Common causes
- Damaged wiring in the brake sensor circuit
- Corroded connectors
- Faulty brake sensor itself
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
No, this code indicates a severe problem with the braking system, so do not drive the vehicle until it is fixed.
Can this code come back after fixing?
Yes, if there's an underlying wiring issue that was not addressed, the code can return.
Why does this fault code appear with other codes?
It often pairs with other brake-related codes indicating multiple faults in the braking system.
Working a real vehicle right now?
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