Brake Pedal Position Sensor Circuit Fault
The brake pedal position sensor is malfunctioning or out of range.
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 pedal position sensor tells the computer how far down the pedal is pressed. If it doesn't send the right signals, the computer can't properly control the brakes or other systems tied to braking.
What the computer is actually seeing
The computer expects a voltage signal that changes from around 0.5 volts (pedal up) to about 4.5 volts (pedal fully pressed) depending on the pedal position. If the signal is outside this range or intermittent, it triggers the code.
What a healthy reading looks like
Expected voltage from the sensor should be between 0.5V and 4.5V based on pedal position. A steady signal is required for proper operation.
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. Visually inspect the wiring and connectors for any damage or corrosion. Repair as necessary. Decision: If no damage is found, proceed to the next step.
- 22. Use a multimeter to measure the voltage at the brake pedal position sensor connector while someone presses the pedal. Check for the expected voltage range (0.5V to 4.5V). Decision: If voltage is within range, consider checking the brake control module. If voltage is out of range, replace the sensor.
- 33. If the sensor was replaced, clear the code and retest the system to see if the code returns. Decision: If the code does not return, the issue is resolved. If it does, further diagnostics on the brake control module may be necessary.
Common causes
- Faulty brake pedal position sensor
- Wiring issues (shorts, opens, poor connections)
- 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 issue soon; the system may not respond correctly to braking, which can be unsafe.
Will this code come back after clearing?
It can come back if the underlying issue isn't resolved. Make sure to check connections and the sensor itself.
Why does this code sometimes appear with C1540?
C1540 relates to a different fault in the brake system, but both codes can indicate issues with the brake pedal sensor or its circuit.
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