C1256high severityChassis
Abnormal Valve Relay Circuit
on 2020 Subaru Legacy 2.5L H4 · AWD
What this code means
The ABS/VDC control module has detected a fault in the valve relay circuit that supplies power to the hydraulic solenoid valves. This prevents proper control of brake pressure during ABS or stability control events.
Symptoms
- ABS warning light on
- Traction/stability control disabled
- Reduced braking assistance
Common causes
- Faulty valve relay inside ABS unit
- Corroded or loose ABS connector
- Blown fuse or power supply fault
- Damaged ABS control module
Diagnostic steps
- Scan ABS module and confirm C1256
- Check ABS fuses and power supply voltage
- Inspect ABS harness and connectors for corrosion
- Test valve relay operation, replace ABS unit if faulty
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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