DTC C1186, C1266 [DSC]


DTC	C1186, C1266		Fail-safe relay
DETECTION CONDITION		• C1186: - Fail-safe relay in DSC HU/CM stuck OFF when ignition switch is turned ON, fail-safe relay ON is commanded. • C1266: - Fail-safe relay in DSC 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 DSC HU/CM terminal C and battery positive terminal • Open or short of fail-safe relay in DSC HU/CM • Stuck fail-safe relay in DSC HU/CM


STEP	INSPECTION		ACTION
1	INSPECT ABS FUSE CONDITION • Is ABS fuse (60 A) normal?	Yes	Go to next step.
1	INSPECT ABS FUSE CONDITION • Is ABS fuse (60 A) normal?	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 DSC HU/CM connector. • Turn ignition key to ON (engine OFF). • Measure voltage between DSC HU/CM terminal C (harness side) and ground. • Is voltage B+?	Yes	Go to next step.
2		No	Repair or replace harness for open circuit between battery positive terminal and DSC HU/CM terminal C, then go to Step 4.
4	VERIFY FAIL-SAFE OPERATION • Turn ignition key to OFF. • Connect all disconnected connectors. • Connect WDS or equivalent to DLC-2. • Turn ignition key to ON (engine OFF). • Access ABS_POWER using WDS or equivalent. • Does fail-safe relay operate?	Yes	Go to next step.
4		No	Replace DSC HU/CM, then go to next step.
5	VERIFY TROUBLESHOOTING COMPLETED • Clear DTC from memory. (See Clearing DTCs Procedures.) • Is same DTC present?	Yes	Replace DSC HU/CM, then go to next step.
5		No	Go to next step.
6	VERIFY THAT NO OTHER DTCS ARE PRESENT • Are any other DTCs output?	Yes	Go to the applicable DTC inspection. (See DTC Table.)
6		No	DTC troubleshooting completed.

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