#
DTC C1186, C1266 [DSC]

id040220806100

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

Diagnostic procedure

STEP | INSPECTION | ACTION
--- | --- | ---
1 | INSPECT ABS FUSE CONDITION • Is ABS fuse (60 A) normal? | Yes | Go to next step.
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.
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.
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.
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.)
No | DTC troubleshooting completed.