C056D code meaning
Brake Pedal Position Sensor Supply Voltage Circuit Low
What C056D means
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).
C056D at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C056D
- Brake system warning and possibly stability lamp
- Regenerative braking reduced, firmer friction braking
- On GM models parking brake messages instead
Common causes of C056D
- Most 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
- Less likelyWeak 5 V regulator in the brake module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Brake pedal position sensorSensor supply
What each part of C056D means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 6D | The exact fault in that area. |
What to do next
- Note C056D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C056D
What does C056D mean?
C056D means "Brake Pedal Position Sensor Supply Voltage Circuit Low". The brake pedal angle sensor of a hybrid or brake-by-wire car is fed from a regulated 5 V line. It is a generic code, so it means the same on every make.
Is it safe to drive with C056D?
Drive gently and only to a workshop. With C056D the car can go into limp mode (reduced power) to protect itself.
Will C056D fail an emissions test?
C056D is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C056D to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will C056D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.