Network, generic

U0544 Invalid Data Received From Parking Assist Control Module B

Check engine lightUsually off

EmissionsNot relevant

Drive cycleNot required

Limp modeNo

Parking assist control modules evaluate the ultrasonic sensors in the bumpers and work out distances or steering paths. Mercedes-Benz lists U0544 in its Intelligent Predictive Repair guide for its eight-gear DCT (models 118, 177, 247; document LI27.00-P-077141): the transmission controller stores U054487 when data from the PARKTRONIC unit are implausible, and failure type 87 points to a missing message. Ford's 2024 OBD summary treats the A unit through U045A, monitored non-MIL inside the PCM on vehicles with Fully Aided Park Assist, which shows that powertrain controllers also check parking data. With U0544 present, expect parking sensors or automatic parking to be switched off and a warning; normal driving is not restricted. Lost communication with module B is U0243.

Likely causes

Internal or software fault in parking assist module B

Messages from module B missing or delayed (bus fault, module reset)

Damaged bumper harness or sensors causing module B to send invalid data

Symptoms

Parking sensors or park assist switched off with warning
Automatic parking manoeuvre not available
Transmission control unit stores the code (Mercedes DCT)

Repair estimate

DifficultyMediumWorkshop job

Parts and labour€0–700

Time0.3–2.5 h

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

Parts involved

parking assist module b

Related codes

U0243 U045A U0159

References: static.nhtsa.gov, fordservicecontent.com, en.wikipedia.org.