U0199
Lost Communication with Door Control Module A
What it means
The Door Control Module has stopped transmitting on the vehicle data bus, so other control units no longer receive its messages. A door control module is silent; its window, lock, and mirror controls fail. Typical causes are loss of power or ground at the module, an open or shorted CAN/LIN bus wire, a connector fault, or an internal module failure.
Is it safe to drive?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Door module unpowered (often broken wires in door hinge)
highOne of the most commonly reported causes for this code — check this first.
Water ingress into door module
mediumA plausible cause — test and verify before replacing parts.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
Related help
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