C0110: Pump Motor Circuit Malfunction

What it means

C0110 indicates a fault in the ABS pump motor circuit. The ABS control module sets it when it detects an electrical problem while monitoring or commanding the pump motor.

How it works

The ABS hydraulic control unit uses an electric pump to restore pressure during anti-lock braking and may use it during stability control. The ABS module monitors the pump’s electrical circuit when it commands the motor; C0110 sets when that circuit does not respond as expected, such as from an open circuit or electrical fault.

Common causes

Most likely first.

1. Open or damaged pump wiring
2. Corroded connector
3. Failed pump motor
4. Blown fuse or poor power supply

Symptoms

• ABS warning light
• Traction or stability control warning
• ABS may be disabled

How to diagnose it

1. Scan the ABS module for related codes and freeze-frame or status data to see whether the fault is current and whether it coincides with a pump command.
2. Check the ABS pump fuse and its power supply for damage or a poor connection, since a blown fuse or missing supply can stop the motor.
3. Inspect the pump motor connector and nearby wiring for corrosion, looseness, abrasion, or breaks.
4. With the vehicle’s service information, check power and ground at the pump circuit under the specified test conditions.
5. If wiring, power, and ground are sound, test the pump motor as specified to determine whether the motor has failed.

Common fixes

• Clean and secure a corroded or loose pump motor connector.
• Repair damaged wiring or a poor ground in the pump motor circuit.
• Replace a failed fuse after finding and addressing the cause of the overload.
• Replace the ABS pump motor or hydraulic control unit if testing confirms an internal failure.

Can I keep driving?

Normal braking may remain, but ABS, traction control, or stability control can be unavailable, so wheels may lock during hard braking and vehicle control may be reduced on slippery roads. Drive cautiously and leave extra stopping distance; avoid hard braking and have the fault checked promptly.