U0201 code meaning
Lost Communication With Door Control Module C
What U0201 means
U0201 stands for door control module C, in the generic list the next door unit after driver (A) and front passenger (B), so on four-door cars usually a rear door. Audi, for example, gives each rear door its own controller (J388, J389, diagnostic addresses 00BB and 00BC), and its Q3 bulletin 2063376 deals with their child lock motors, but no Audi document names U0201. No manufacturer documents this code publicly. The number also has a history: GM's 2011 code list for the Saab 9-5 assigns U0201 to the transfer case controller instead, so on older GM vehicles the scan tool's own text decides. Where it means a door, expect a rear window, lock or child lock that no longer responds; a chafed harness at the door hinge is a frequent reason. U0502 covers invalid data.
U0201 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0201
- Rear window, lock or child lock inoperative
- Door or child lock warning in the cluster
Common causes of U0201
- Most likelyChafed or broken wires in the rear door hinge harness
- PossibleLoose or corroded pins in the door connector
- Less likelyRear door control module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Door module cCAN bus
What each part of U0201 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 01 | The exact fault in that area. |
What to do next
- Note U0201 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 U0201
What does U0201 mean?
U0201 means "Lost Communication With Door Control Module C". U0201 stands for door control module C, in the generic list the next door unit after driver (A) and front passenger (B), so on four-door cars usually a rear door. It is a generic code, so it means the same on every make.
Is it safe to drive with U0201?
U0201 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0201 fail an emissions test?
U0201 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 U0201 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U0201 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.