C0265 on Chevrolet: How to Diagnose & Fix
EBCM Motor Relay Circuit Low When On
4 Chevrolet models · 4 documented issues · 2 critical · $100-$1,200 repair
C0265 on Chevrolet by model: symptoms, diagnosis and fix
The S-series Blazer's Kelsey-Hayes ABS system is prone to age-related faults: front wheel-speed sensors (integrated into the hub bearings) corrode and give erratic signals, the EBCM ground at the radiator support gets rusty/loose, and later Kelsey-Hayes 325 modules can fail internally. Symptoms include an ABS warning light, erratic wheel-speed codes, and in some cases the ABS pump running with the key off. Corroded grounds and connectors are a very common root cause on rust-belt trucks.
Common Symptoms
- ABS warning light on
- Erratic or dropped wheel-speed signal
- ABS activating at low speed / false activation
- ABS pump running with the ignition off
- Intermittent faults that worsen when wet
How to Fix
Scan for C-codes and inspect. Clean and tighten the EBCM ground straps at the radiator support first. Replace corroded front wheel-speed sensors / hub bearing assemblies as needed. If the EBCM itself is faulty, a repair-and-return board service is a cost-effective alternative to a new module.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- ABS Wheel Speed SensorCross-ref241-1060
Fitment confirmed against the ShowMeTheParts catalog for this vehicle's year and engine.
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Sources for this issue (1)
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)
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)
A known safety issue on later first-generation Equinox models involves corrosion in the brake pressure modulator valve (BPMV), which can cause the ABS to activate improperly at low speeds. Owners report a sudden buzzing pedal, unexpected increase in stopping distance, and the vehicle seeming to roll through a stop on dry pavement. This problem was serious enough to trigger a GM safety recall in salt-belt states.
Common Symptoms
- ABS activates at low speed on dry pavement
- buzzing brake pedal
- extended stopping distance
- unexpected pedal pulsation
- ABS warning light in some cases
How to Fix
Diagnosis includes scanning the ABS module, checking wheel speed sensor data, and inspecting whether the vehicle falls under the recall population. The recall remedy involved installing a corrosion-resistant protective coating and, in some cases, replacing the BPMV. If the recall has not been completed, owners should verify VIN status with GM or NHTSA immediately.
Sources for this issue (1)
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 on a Chevrolet?
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. On Chevrolet it is documented across 4 models: Blazer, Tahoe, Monte Carlo, Equinox.
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 on a Chevrolet?
Published repair estimates on Chevrolet range from $100 to $1,200 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for C0265 on a different make?
View C0265 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.