Network, generic

U020A Lost Communication With Moveable Roof Control Module B

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

U020A stands for moveable roof control module B, a second roof unit beside module A (U0207); which drive it controls, for instance a separate sunshade or a further glass panel, depends on the maker. No manufacturer documents this code publicly. Related service experience comes from roof modules in general: Kia service action SA595 (bulletin 363, 2025 K4) updates the roof control module because a software logic error left the sunroof unable to open or close, and the update contains a reset of the module for sunroof initialisation. Power roofs usually need such a re-learn after a power loss or module replacement before they travel fully again. Invalid data from unit B is U050B. No MIL.

Likely causes

Roof module software or missing initialisation
Wet or corroded connector in the headliner
Fuse or ground of roof module B
Roof module B faulty

Symptoms

  • Second roof panel or sunshade does not move
  • Roof stops halfway or needs repeated button presses

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€0–900
Time0.3–3 h

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

Parts involved

moveable roof module bcan bus

Related codes

U0207U0206U050B

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