U0503Invalid Data Received From Door Control Module D
- Generic OBD-II code · Network
- How the car detects it
- U0503 is the invalid-data code for door control module D. It is rarely seen in published service material: Ford, the most visible user of lettered door modules, labels the latch controllers of its four-door electronic-latch cars E to H (DCME–DCMH, e.g. Mustang Mach-E), leaving D unused there. In a four-door car with one unit per door, D would typically be the last of the four, but that is not fixed. When a receiver gets D's lock, window or switch data and the content fails its checks, the code is stored; if the frames stop, U0202 follows. No manufacturer documents U0503 publicly. Expect a single door with an unreliable lock, window or interior switch rather than a car-wide fault.
- What you may notice
- One door not unlocking or locking with the others
- Window switch on that door ignored
- Likely causes
- PossibleDoor control module D internally faulty or water-damaged
- PossibleBroken data lead in the door harness grommet
- RareWeak 12 V battery causing faulty frames during wake-up
- Repair
- Medium · Usually a job for a workshop.Typical cost: €0 – €500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.