Network, generic

U028F Lost Communication With Active Aerodynamic Feature Control Module C

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

A third aerodynamic control module, C, is found on vehicles that combine front elements with rear ones such as a deployable spoiler or an adjustable wing. Sports cars show what these rear parts do: the 2017–2019 Ford GT raises and lowers an active aero wing, and Ford's bulletin 20-2353 deals with that wing touching the body after long storage in its lowered position. U028F is stored when the network loses module C altogether, so the element neither reports its position nor accepts commands. No manufacturer documents U028F or links letter C to a particular element. A wing that stays down reduces downforce at speed, one that stays up adds drag. CARB counts movable aero parts among the off-cycle technologies with logged operating time.

Likely causes

Wiring chafed or broken at the moving rear element
Moisture in the connector of module C
Fuse, supply or ground of module C faulty
Module C internally failed

Symptoms

  • Spoiler or wing no longer moves
  • Active aero fault message, sometimes a speed limitation

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–2,000
Time0.3–4 h

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

Parts involved

active aero module cvehicle bus wiring

Related codes

U028DU028EU0290

References: static.nhtsa.gov, law.cornell.edu.