Network, generic

U054A Invalid Data Received From Entertainment Control Module — Rear B

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Some vehicles carry two rear entertainment units, for instance one screen per front headrest or separate units for second and third rows, which J2012 numbers Rear A and Rear B. GM's Saab 9-5 code list shows such a split: U0196 for the rear audio control module and U0249, the lost-communication partner of U054A, for a rear radio audio control module. A GM patent on reprogramming modules notes that rear-seat entertainment often sits on a fast MOST entertainment bus rather than on CAN. U054A means unit B still sends, but its status or control data are rejected; for unit A the code would be U0497. No public bulletin names U054A. Usually only the second rear screen, its headphone channel or its remote control stops working.

Likely causes

Rear entertainment unit B internally faulty
Strained wiring through seat, headrest or headliner to unit B
Software level of unit B not matching the front unit

Symptoms

  • Second rear screen shows no picture or wrong source
  • Headphones or remote of that screen do not respond

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–1,200
Time0.5–3 h

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

Parts involved

rear entertainment module b

Related codes

U0249U0497U0546

References: saabwisonline.com, patents.google.com, patents.google.com.