C0280 C0xxx · Chassis (C) High severity
Brake Pedal Position / Travel Sensor Fault
The ECU cannot trust the brake pedal input, which affects brake light operation, regenerative blending on hybrids and EVs, and stability logic.
Severity guidance: High — stop driving and diagnose now; risk of further damage
Symptoms you will notice
- Brake lights not working or always on
- Regenerative braking inconsistent
- Cannot shift out of park on some vehicles
Common causes
Ordered from most to least likely — start at the top.
- 1 Failed pedal position sensor
- 2 Misadjusted switch
- 3 Wiring fault
- 4 Software calibration lost
How to diagnose it
Cheapest and least invasive first — most of these codes are not a parts problem.
- ✓ Watch brake switch state in live data while pressing the pedal — check both stages if fitted.
- ✓ Confirm the brake lights actually operate.
- ✓ Adjust or replace the switch, then recalibrate if required.
- ✓ On hybrids/EVs, verify regen blending returns after the repair.
Repair options
- Replace or adjust the brake pedal switch
- Repair the wiring
- Recalibrate the pedal sensor
C0280 — frequently asked questions
Can it stop me selecting gear? +
Yes — most automatic vehicles require a valid brake signal before releasing the shift interlock.
Why does regen feel wrong? +
The ECU blends friction and regenerative braking from pedal position; a bad signal breaks the blend.
Confirm the diagnosis before you buy parts
Send us the code, freeze-frame data and the vehicle — our engineers will tell you what to test first.