C0265: How to Diagnose & Fix — EBCM Motor Relay Circuit Low When On
4 vehicles · 2 makes · $100-$1,200 repair
How to diagnose and fix C0265: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Chevrolet Monte Carlo · 2000–2007
The Electronic Brake Control Module (EBCM) mounted on the ABS hydraulic unit is prone to failure due to internal solder joint cracking from vibration and thermal cycling. When it fails, ABS, traction control, and stability control all stop functioning. The brake warning light, ABS light, and traction control light all illuminate.
Common Symptoms
- ABS light on
- Traction control light on
- Service stability system message
- Loss of ABS function
- Brake pedal pulsation during normal braking
How to Fix
The EBCM can be sent to a rebuilder for solder repair and reprogramming, which is more affordable than dealer replacement. Alternatively, replace the ABS modulator assembly. After replacement, the module must be programmed to the vehicle VIN. Bleeding the ABS system requires a scan tool to cycle the pump and valves.
Sources for this issue (1)
Cadillac Eldorado · 1992–2002
The Bosch ABS/traction control modulator assembly develops internal leaks and electronic failures, disabling ABS and traction control. The modulator is expensive and integrates the hydraulic pump, valves, and electronic controller into one unit. Moisture intrusion into the electrical connector accelerates failure.
Common Symptoms
- ABS light on
- Traction control disabled message
- Brake pedal drops under ABS activation
- ABS motor runs continuously for short periods
How to Fix
The ABS modulator can be sent to a specialty rebuilder for significantly less than dealer replacement cost. Apply dielectric grease to all electrical connectors during reinstallation. Bleed the ABS system using a scan tool to cycle the pump and valves. Inspect the wheel speed sensors and tone rings during the repair.
Sources for this issue (1)
Chevrolet Tahoe · 2000–2006
GMT800 Tahoes commonly light the ABS, Traction Control and (on later trucks) StabiliTrak warnings simultaneously due to the Electronic Brake Control Module (EBCM) or, very often, its corroded frame-mounted ground. The dedicated EBCM ground on the driver-side frame rail is exposed to road salt and corrodes, causing intermittent module communication loss and codes like C0265. Internal EBCM solder-joint failures also occur. Normal service braking still works, but ABS/traction functions drop out.
Common Symptoms
- ABS, Traction and StabiliTrak lights on together
- Speedometer dropout or erratic (shared circuit)
- Code C0265 / loss of module communication
- ABS inoperative but normal pedal braking
- Intermittent lights that come and go over bumps
How to Fix
Pull chassis 'C' codes first. Before condemning the module, locate and clean/re-terminate the EBCM ground on the frame rail (a cheap, common fix). If the module itself is at fault (C0265/C0110 with confirmed internal fault), options are a rebuild/repair service for the EBCM or a replacement module that must be programmed to the VIN. Inspect the wheel-speed sensor circuits as well. Ground repair can be under $100; module rebuild/replacement runs several hundred.
Sources for this issue (1)
Chevrolet Blazer · 1995–1999
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C0265 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does C0265 mean?
C0265 stands for "EBCM Motor Relay Circuit Low When On." C0265 is a manufacturer-specific chassis code (common on GM vehicles) indicating the Electronic Brake Control Module (EBCM) detected a fault in the internal motor relay circuit that powers the ABS pump motor, reading low voltage when the relay should be on. This relay must energize for the ABS, traction control, and stability systems to operate. When this fault is present, the module typically disables ABS and traction/stability control, illuminating the related warning lights. Normal braking still works, but the anti-lock and stability assist functions are offline.
What are the most common causes of C0265?
The most common causes of C0265 are: Cracked solder joints / internal failure in the EBCM, Failed ABS pump motor relay, Damaged or corroded EBCM wiring/connectors, Low system voltage or weak battery/charging fault, Poor ground at the EBCM, Failed ABS pump motor, Corrosion or water intrusion in the module connector. The specific cause varies by vehicle.
How much does it cost to fix C0265?
Repair costs for C0265 range from $100 to $1,200, depending on the vehicle and root cause.
Which vehicles are affected by C0265?
Au7o has documented C0265 across 4 vehicle models from 2 manufacturers: Cadillac, Chevrolet.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.