C1104high severityChassis
Pump Motor Circuit Fault
on 1993-2001 Subaru Impreza 2.2L H4 · AWD
What this code means
A fault is detected in the ABS pump motor or its circuit. The pump may not build pressure during ABS activation.
Symptoms
- ABS warning light on
- ABS not functioning
- No pump noise during self-test
Common causes
- Failed pump motor
- Open or shorted motor wiring
- Bad motor relay
- Faulty ABS module driver
Diagnostic steps
- Command pump motor with scan tool
- Check motor power and ground
- Test motor resistance
- Replace pump motor or repair wiring
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C0021
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C0025
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C0026
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C0028
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C0035
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C0036
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