Network, generic

U055D Invalid Data Received From Special Purpose Vehicle Control Module D

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U055D is the last of the four special purpose controller codes. It is stored when frames from controller D reach the network but carry values the receiver rejects. No manufacturer documents it; even Ford, which names slot A in its 2024 summary as a non-MIL check, says nothing about B to D. In practice the code is most likely on heavily converted vehicles with several add-on units, where one controller may feed implausible values after a voltage dip, a partial software update or a wiring change. Unlike U025C, the lost-communication code, the controller is still transmitting, so power and ground are usually present and the content of the data is what needs checking. Driving is not normally restricted.

Likely causes

Incomplete or interrupted software update of controller D
Voltage dip from heavy conversion loads corrupting controller D's output
Controller D internally faulty

Symptoms

  • Individual conversion functions fail intermittently
  • Fault entry without effect on engine or brakes

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€80–600
Time0.5–3 h

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

Parts involved

special purpose vehicle module d

Related codes

U025CU055AU055BU055C

References: fordservicecontent.com, serdia.deutz.com.