ABS Pump Motor Circuit Open
What does C0115 mean?
The C0115 code means the vehicle's onboard diagnostic system has detected: ABS Pump Motor Circuit Open. This is a critical severity code.
Common Symptoms
- ABS warning light on
- No ABS function when braking hard
- Traction control disabled
- Stability control light on
- Brake pedal feels normal but ABS does not engage
Probable Causes (Ranked by Likelihood)
- Open circuit in ABS pump motor winding Very High
- Blown ABS pump motor fuse or relay High
- Corroded pump motor electrical connector Moderate
- Broken wire in pump motor circuit Moderate
- ABS control module driver circuit failure Low
Step-by-Step Diagnostic Procedure
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Check the ABS pump motor fuse and relay first
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Test for voltage at the pump motor connector when ABS is commanded on
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Measure pump motor winding resistance -- an open circuit reads infinite ohms
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Inspect the connector and wiring for corrosion or damage
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Swap the ABS relay with a known good relay of the same type
Frequently Asked Questions
What does an open circuit mean for the ABS pump?
An open circuit means electrical continuity is broken somewhere in the pump motor circuit. The module cannot power the pump, so ABS cannot build the hydraulic pressure needed to modulate braking.
Could a blown fuse cause C0115?
Yes. A blown ABS pump motor fuse is one of the simplest causes of this code. Always check fuses and relays first before condemning the pump motor itself.
Can I repair the ABS pump motor wiring?
If the open circuit is in the wiring harness rather than inside the pump motor itself, yes. Repair the damaged wire and ensure all connections are clean and tight. If the motor winding is open internally, the pump motor must be replaced.