U0188
Lost Communication with Audio Rear Control Module
What it means
The Audio Rear Control Module has stopped transmitting on the vehicle data bus, so other control units no longer receive its messages. Rear-seat audio controls stop working. 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
Rear audio module unpowered
highOne of the most commonly reported causes for this code — check this first.
CAN wiring to rear audio module broken
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
Get the full diagnosis
Add your vehicle and see step-by-step repair help, recalls, and TSBs in Wrenchify.
Diagnose U0188 freeNo credit card required