C1101high severityChassis
ABS Control Module Internal Fault
on 2020 Subaru Legacy 2.5L H4 · AWD
What this code means
The ABS control module has detected an internal electronic failure. No direct OBD P-code equivalent exists; this is a manufacturer chassis code.
Symptoms
- ABS warning light on
- ABS system disabled
- Possible brake/traction light on
Common causes
- Failed ABS control module
- Internal memory/processor fault
- Corroded module connector
- Water intrusion into module
Diagnostic steps
- Scan for ABS trouble codes
- Check module power and ground
- Inspect connector for corrosion
- Replace ABS module if internal fault confirmed
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Other Chassis codes on this vehicle
C0021
LF Wheel Speed Sensor Range/Performance
C0022
RF Wheel Speed Sensor Range/Performance
C0023
LR Wheel Speed Sensor Range/Performance
C0024
RR Wheel Speed Sensor Range/Performance
C0025
LF Wheel Speed Sensor Circuit Intermittent
C0026
RF Wheel Speed Sensor Circuit Intermittent
C0027
LR Wheel Speed Sensor Circuit Intermittent
C0028
RR Wheel Speed Sensor Circuit Intermittent
C0035
Left Front Wheel Speed Sensor Circuit
C0036
Left Front Wheel Speed Signal Erratic