Network, generic

U0201 Lost Communication With Door Control Module C

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

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.

Likely causes

Chafed or broken wires in the rear door hinge harness
Loose or corroded pins in the door connector
Rear door control module faulty

Symptoms

  • Rear window, lock or child lock inoperative
  • Door or child lock warning in the cluster

Repair estimate

DifficultyMediumDIY possible
Parts and labour€0–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

door module ccan bus

Related codes

U0200U0202U0502U0102

References: saabwisonline.com, static.nhtsa.gov, patents.google.com.