You can drive to get it fixed since normal braking remains, but with ABS and stability control disabled the vehicle can lock a wheel or skid in hard or low-grip stops. Brake gently, leave extra distance, and repair it promptly. On General Motors vehicles C0265 means the electronic brake control module (EBCM) has detected a fault in its relay circuit — the internal relay that feeds high-current battery power to the ABS pump motor and solenoid valves. When it sets, the module switches off ABS, traction and stability control for that ignition cycle and lights the brake-system warnings, though normal (base) hydraulic braking still works.
What C0265 means
C0265 is a manufacturer-specific chassis (C) code. On General Motors vehicles it flags a fault in the electronic brake control module (EBCM) relay circuit — the module-internal relay that supplies the ABS pump motor and solenoids. Because the relay is inside the EBCM it is not separately serviceable. See the make-specific page below for the full GM diagnosis.
Symptoms
- Amber ABS warning light stays on, usually alongside the traction-control and StabiliTrak/ESC indicators
- A 'Service Brake System', 'Service Traction Control' or 'Service StabiliTrak' message appears in the driver information center
- Anti-lock, traction and stability control are inoperative — the pedal no longer pulses on a hard or slippery stop
- The red BRAKE warning may also illuminate on some GM models when ABS is disabled
- Base braking still feels normal, but wheels can lock earlier during emergency or low-grip stops
Common causes
- Failed or intermittent EBCM internal relay (solenoid or pump-motor relay) — the relay is built into the module and is not separately replaceable
- Loss of the high-current battery (B+) feed to the EBCM: blown ABS maxi-fuse/fusible link or an open in the supply wire
- Corroded, loose or backed-out terminals in the EBCM power/ground connector, giving high resistance on the feed or ground
- Poor or open ground for the module/pump circuit at the body or frame ground point
- Low system voltage — a weak battery or failing charging system dropping the feed below the roughly 10 V the module needs to run the test
- Water intrusion or corrosion inside the EBCM or its harness connector after underbody exposure
- A wiring short-to-ground on the relay control or power circuit
Severity & driving advice
Severity: High — Base brakes still work, but ABS, traction and stability control are switched off, so stopping distances lengthen on slippery or emergency stops.
Can I drive? You can drive to get it fixed since normal braking remains, but with ABS and stability control disabled the vehicle can lock a wheel or skid in hard or low-grip stops. Brake gently, leave extra distance, and repair it promptly.
FAQ
Can I still brake safely with a C0265 code?
Yes, your ordinary hydraulic brakes still work normally — pushing the pedal still stops the car. What you lose is the anti-lock, traction and stability functions, because the EBCM shuts them off when it can't trust the relay circuit. That means a wheel can lock up in a panic or low-grip stop, so brake earlier and more gently and keep extra following distance until it's repaired.
Is C0265 a relay I can just swap out?
No. On GM vehicles the ABS relays are built inside the electronic brake control module (EBCM) and are labeled non-serviceable, so there is no separate relay to replace. If the relay circuit itself has failed after the power feed, grounds, fuses and connector all check good, the fix is to replace the EBCM (often the combined EBCM and brake pressure modulator valve assembly).
Could a weak battery cause C0265?
It can. The EBCM only runs its relay test when the feed is above roughly 10 volts, and it needs a strong high-current supply to drive the pump motor. A weak battery, a failing alternator, or corroded power and ground connections can drop the voltage enough to set C0265 even though the module is fine, so always verify charging-system voltage and the ABS power feed before replacing anything.
Why did the traction control and StabiliTrak lights come on too?
Traction control and StabiliTrak rely on the same EBCM and the same pump motor and solenoids as ABS. When C0265 sets, the module disables all of those functions together for the rest of the ignition cycle, so their warning lights and any 'Service' messages come on at the same time as the ABS light. They should all clear once the relay-circuit fault is repaired.
Will C0265 clear by itself?
If the cause was a brief voltage dip, the code may go to history and the lights may go out on the next clean ignition cycle. But if the relay circuit, feed or ground has a real fault, it will reset and the ABS, traction and stability systems will stay off. Have the actual cause diagnosed rather than relying on it clearing on its own.