C0265 C0xxx · Chassis (C) High severity
ABS/ESP Control Module Relay or Power Circuit
The ABS module's power supply or internal relay is not behaving. A supply problem masquerading as a module failure in most cases.
Severity guidance: High — stop driving and diagnose now; risk of further damage
Symptoms you will notice
- ABS lamp on
- Module not communicating
- Multiple chassis codes at once
Common causes
Ordered from most to least likely — start at the top.
- 1 Blown fuse or failed relay
- 2 Corroded connector at the modulator
- 3 Poor earth
- 4 Internal module fault
How to diagnose it
Cheapest and least invasive first — most of these codes are not a parts problem.
- ✓ Check every ABS-related fuse and relay before anything else.
- ✓ Measure voltage drop on the module supply and earth under load.
- ✓ Inspect the connector for water ingress — ABS connectors live in a harsh location.
- ✓ Only then consider module replacement.
Repair options
- Replace the fuse or relay
- Repair the wiring or earth
- Replace the module if genuinely failed
C0265 — frequently asked questions
Several chassis codes appeared at once — why? +
A shared power or earth fault. Do not chase each code individually; fix the supply first.
Is water ingress common? +
Yes, especially where the connector sits low in the engine bay. Seal it after repair.
Confirm the diagnosis before you buy parts
Send us the code, freeze-frame data and the vehicle — our engineers will tell you what to test first.