Chassis, generic

C05E8 4WD/AWD Clutch B Actuator Control Circuit Performance

Check engine lightUsually off
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

The clutch B actuator circuit is electrically intact, yet its response does not match the command: current, motor movement or the torque built up stays outside the expected band. Ford stores C05E8:71 in the AWD module of 2021–2022 Bronco Sport 2.0L vehicles (SSM 51117), together with C05D9:71 for clutch A; both lead back to the misaligned magnet ring of the rear drive unit motor, and the repair is a new motor instead of a complete unit. On twin-clutch modules such as GKN's Twinster each wheel clutch is set separately; GKN's actuator controller compensates for wear and runs its own self-diagnosis, so a clutch that lags behind its partner stands out. Once one side no longer follows, left-right torque control is lost and AWD is usually switched off for the trip.

Likely causes

Misaligned magnet ring in the rear drive unit motor (Ford Bronco Sport 2.0L)
Worn or sluggish actuator motor or hydraulic control for clutch B
Low battery voltage limiting actuator current
Binding in the actuator mechanism or clutch pack

Symptoms

  • AWD fault message, all-wheel drive off for the rest of the trip
  • Reduced traction off-road because one rear wheel is no longer controlled

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€100–1,500
Time0.5–4 h

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

Parts involved

awd clutch b actuatorawd control module

Related codes

C05E7C05E9C05EAC05D9

References: static.nhtsa.gov, mobilityengineeringtech.com, just-auto.com.