Brake Pedal Position Sensor Circuit Malfunction
The brake pedal position sensor is not functioning as expected.
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 sends the signal of how far the brake pedal is pressed. If it's faulty, the system can't tell if you're braking properly, which can affect the overall braking system performance.
What the computer is actually seeing
The ECU expects the brake pedal voltage signal to vary between 0.5 to 4.5 volts when the pedal is pressed. If it stays constant or outside this range, it triggers the code.
What a healthy reading looks like
0.5V (off) to 4.5V (fully pressed), with the expected change corresponding to the pedal position.
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.
- 1Inspect the wiring and connectors related to the brake pedal position sensor for damage or corrosion. If found, repair or replace as needed.
- 2Check the brake pedal position sensor output voltage at the connector. It should be between 0.5V (pedal not pressed) and 4.5V (pedal fully pressed). If out of this range, the sensor may be faulty.
- 3If the sensor looks good and functions within expected values, check the ECU for fault codes or software updates.
Common causes
- Wiring issues (damaged insulation, corrosion)
- Faulty brake pedal position sensor
- Bad connection at the sensor or ECU
- ECU software error
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
It's moderately serious; you should fix it soon since it can affect braking performance.
Will the code come back after clearing it?
If the underlying issue isn't resolved, yes, it will likely return.
Why does this code appear alongside C1100?
C1100 indicates a general circuit issue, while C1103 specifies a problem with the position signal itself.
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