C0266 Code: Meaning, Causes, and Symptoms | OBD2 Codes
C0266 – EBCM Motor Relay Circuit High When Off
C0266 Possible Symptoms
Anti-Lock Brake System (ABS) Warning Light ON,Engine Light ON (or Service Engine Soon Warning Light)
C0266 Possible Causes
Faulty Electronic Brake Control Module (EBCM),Electronic Brake Control Module (EBCM) harness is open or shorted,Electronic Brake Control Module (EBCM) circuit poor electrical connection
The ABS relay supplies battery voltage to six valve solenoids (RF dump/isolation, LF dump/isolation, and rear dump/isolation). The Electronic Brake Control Module (EBCM) microprocessor applies the grounds needed to activate each solenoid. The low side of each solenoid coil has a feedback circuit to the EBCM microprocessor. When a solenoid is commanded OFF, the feedback voltage is high. When a solenoid is commanded ON, the feedback voltage is low.