Chassis, generic

C00A1 Driveline Control Module

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

This umbrella code concerns the driveline control module itself, often called AWD or 4WD module, not one of its outputs or sensors. It covers internal faults such as memory or processor errors, a missing or poor supply and ground, or software and configuration problems that stop the module from controlling clutches, transfer case or disconnects. GKN describes such controllers as layered software, from operating system through actuator drivers up to vehicle functions; BorgWarner builds the electronics straight into the brushless actuator of its coupling. Ford gives a code-specific example: SSM 51659 covers 2023 F-Super Duty trucks built up to 9 May 2023 that store C00A1 in their AWD module or lose four-wheel drive, and asks to check that ground G239, under the right-hand front sill trim close to the BCM, is tightened to 8 Nm.

Likely causes

Loose or corroded module ground (Ford G239 on 2023 Super Duty)
Low battery voltage or poor supply to the module
Module software or configuration fault, update or reprogramming needed
Internal failure of the driveline control module

Symptoms

  • Four-wheel drive inoperative
  • 4WD/AWD warning or service message
  • Further driveline codes or lost communication with the module

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€40–1,200
Time0.3–3 h

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

Parts involved

driveline module

Related codes

C00A2C00A3C00A4C00A5U041E

References: static.nhtsa.gov, mobilityengineeringtech.com, borgwarner.com.