DTC C1186, C1266 [ABS/TCS]


DTC	C1186, C1266		Fail-safe relay
DETECTION CONDITION		• C1186: - Fail-safe relay in ABS (ABS/TCS) HU/CM stuck OFF when ignition switch is turned ON, fail-safe relay ON is commanded. • C1266: - Fail-safe relay in ABS (ABS/TCS) HU/CM stuck ON when ignition switch is turned ON, fail-safe relay OFF is commanded.
POSSIBLE CAUSE		• Malfunction of fuse (ABS 60 A) • Open circuit in harness between ABS (ABS/TCS) HU/CM terminal AA and battery positive terminal • Open or short of fail-safe relay in ABS (ABS/TCS) HU/CM • Stuck fail-safe relay in ABS (ABS/TCS) HU/CM


STEP	INSPECTION		ACTION
1	INSPECT ABS FUSE CONDITION • Is ABS fuse (60 A) okay?	Yes	Go to next step.
1	INSPECT ABS FUSE CONDITION • Is ABS fuse (60 A) okay?	No	Replace fuse, then go to Step 4.
2	INSPECT FAIL-SAFE RELAY POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT • Turn ignition key to OFF. • Disconnect ABS (ABS/TCS) HU/CM connector. • Connect SST (adapter harness) to ABS (ABS/TCS) HU/CM connector (harness side only). • Turn ignition key to ON (engine OFF). • Measure voltage between ABS (ABS/TCS) HU/CM terminal AA (harness side) of SST and ground. • Is voltage B+?	Yes	Go to next step.
2		No	Repair or replace harness for open circuit between battery positive terminal and ABS (ABS/TCS) HU/CM terminal AA, then go to Step 4.
3	VERIFY FAIL-SAFE OPERATION • Turn ignition key to OFF. • Remove SST (adapter harness) and connect all disconnected connectors. • Connect WDS or equivalent to DLC-2. • Turn ignition key to ON (engine OFF). • Access ABS_VOLT using WDS or equivalent. • Does fail-safe relay operate?	Yes	Go to next step.
3		No	Replace ABS (ABS/TCS) HU/CM, then go to next step.
4	VERIFY TROUBLESHOOTING COMPLETED • Clear DTC from memory. (See Clearing DTCs Procedures) • Is same DTC present?	Yes	Replace ABS (ABS/TCS) HU/CM, then go to next step.
4		No	Go to next step.
5	VERIFY AFTER REPAIR PROCEDURE • Is there any other DTC present?	Yes	Go to applicable DTC inspection.
5		No	Troubleshooting completed.