OBD-II code · Chassis
C0099 ABS Control Module Internal Fault
The ABS control module fails its internal self-test (RAM, ROM or processor watchdog). ABS and stability control are disabled.
Is it safe to drive with C0099?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyModule internally failed
- PossiblePower supply undervoltage during operation
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
- 1–4 h
- Emissions test
- Usually unaffected
- Parts involved
- ABS Control Module
Related codes
- C00964WD/AWD Rear Differential Unit Actuator A Data
- C00974WD/AWD Rear Differential Unit Actuator B
- C00984WD/AWD Rear Differential Unit Actuator B Data
- C009A4WD/AWD Rear Differential Unit Actuator A Position Sensor B
- C009B4WD/AWD Rear Differential Unit Actuator A Position Sensor C
- C009C4WD/AWD Rear Differential Unit Actuator A Position Sensor Correlation
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.