C056DBrake Pedal Position Sensor Supply Voltage Circuit Low
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- The brake pedal angle sensor of a hybrid or brake-by-wire car is fed from a regulated 5 V line. C056D means this supply is present but sagging. Ford's 2015–2019 hybrid summaries set a joint window for C056D and C056E: if the supply leaves 4.87–5.13 V for 50 ms, the code for the low or high side is stored; in Ford's ABS module both appear as C100F and the hybrid powertrain module shows C056D for the low case. A drooping reference usually means a short to ground inside the sensor, a damaged supply wire or another load on the same rail. GM uses C056D in its own way, for example with parking brake faults on 2017–2019 Acadia, Traverse, Enclave and XT5 (PIT5662A).
- What you may notice
- Brake system warning and possibly stability lamp
- Regenerative braking reduced, firmer friction braking
- On GM models parking brake messages instead
- Likely causes
- LikelyPedal sensor loading the supply through an internal fault
- PossibleSupply wire chafed to ground near the pedal box
- PossibleAnother sensor on the same 5 V rail pulling it down
- RareWeak 5 V regulator in the brake module
- Repair
- Medium · Usually a job for a workshop.Typical cost: €40 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.