OBD-II code · Chassis
C00A4 Driveline Control Module Rear Differential Unit B Control Circuit Driver
Fault on driveline control module driver for rear differential unit B.
Is it safe to drive with C00A4?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyInternal driver fault
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Usually unaffected
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Driveline Module, Rear Diff Actuator B
Related codes
- C00A3Driveline Control Module Rear Differential Unit A Control Circuit Driver
- C00A1Driveline Control Module
- C00A2Driveline Control Module Power Transfer Unit Control Circuit Driver
- C00A5Driveline Control Module Transfer Case Unit Control Circuit Driver
- C00A64WD/AWD Transfer Case Unit Actuator
- C00A74WD/AWD Transfer Case Unit Actuator Position Sensor A
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.