U0200
Lost Communication With Door Control Module B
Communication network (body)
Generic OBD-II
Low
What it means
U0200 means the network has lost communication with door control module B — the unit that runs a door's powered features like the window, lock, and mirror. It doesn't affect how the car drives; the main symptom is that door's controls not working. A common cause is a broken wire in the door-jamb harness where it flexes each time the door opens.
Low
Can I keep driving? Safe to drive — this affects a door's powered features (window, lock, mirror). It doesn't change how the car runs, though a door's controls may not work.
Common symptoms
What you'll notice
- Power window, lock, or mirror on the affected door not working
- Warning message about a door or body-control feature
- Door control module B not responding to a scan tool
- Intermittent operation of that door's controls
Common causes
Most likely first
- Loss of power or ground to door control module BLikely
- Blown fuse feeding the moduleCommon
- Broken or corroded wiring in the door jamb harness (a common flex point)Common
- Loose or corroded connectors, or water intrusion in the doorLess often
- Failed door control moduleLess often
How to diagnose & fix
Work through it in order
- Scan all modules and confirm door control module B is unreachable.
- Check battery voltage and the module's fuse, power, and ground feeds first.
- Inspect the door-jamb harness where it flexes between the body and door for broken wires.
- Check the module's connectors for corrosion, looseness, or water intrusion.
- If power, grounds, and wiring are good, suspect the module — replace and program it as required, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with U0200?+
Yes — the car runs normally. You may just lose power window, lock, or mirror function on that door until it's fixed.
Can I just clear U0200?+
You can, but it returns unless the module's power, ground, wiring (often a broken door-jamb wire), or the unit itself is repaired.
Related codes
Often seen with U0200
Read & clear U0200 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX