C0110

C0110 indicates an ABS pump motor circuit malfunction — the EBCM is commanding the hydraulic pump motor to run (during self-test or active ABS event) and either not seeing the expected current draw, seeing a stuck-on condition, or detecting a control-circuit fault. This is one of the few ABS codes where the cheapest-first ladder is short, because the pump motor itself is usually integral to the EBCM/hydraulic control unit (HCU) assembly. Start with the free checks: clear the code, cycle the key three times and listen for the pump self-test (a 1-2 second whirr on most GM/Ford applications); silence usually means the motor or its relay is dead. Check the ABS pump motor fuse and the dedicated battery-feed circuit — pump motors pull 30-50 amps in operation and run on a thick fusible link straight from the battery; corrosion at the underhood fuse block is a $0 fix that masquerades as a $1,200 EBCM. Measure battery voltage at the pump motor connector with the relay commanded on via scan tool: anything under 11.5V under load points to a wiring/ground issue, while full battery voltage with no motor rotation means the motor armature is open or seized. The expensive misdiagnosis: replacing the entire EBCM/HCU at $900-$1,500 when the actual fault was a corroded pump-motor ground stud at the inner fender, an $8 repair.

Vehicle-specific patterns: 1999-2007 GM full-size trucks (Silverado, Sierra, Tahoe, Suburban, Yukon) with Kelsey-Hayes 325 EBCM — pump motor brushes wear and the solder joints inside the EBCM crack, classic C0110 plus C0265 combo; Module Masters and several remanufacturers offer a $150-$250 rebuild service vs $900+ for new. 2005-2010 Pontiac G6/Chevy Malibu — pump motor ground at the radiator support corrodes. 2003-2008 Dodge Ram 1500/2500 — pump motor connector backshell cracks, water enters. 2000-2005 Ford Excursion/F-250 Super Duty — pump motor relay in the underhood fuse box welds contacts. Estimated repair: $8 to $1,500.