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 DTC C1186, C1266 [ABS (ABS/TCS)]

DTC C1186, C1266 [ABS (ABS/TCS)]

id040214806100

DTC

C1186, C1266

Fail-safe relay

DETECTION CONDITION

• C1186:
- Fail-safe relay in ABS (ABS/TCS) HU/CM stuck OFF when ignition key is turned ON, fail-safe relay ON is commanded.
• C1266:
- Fail-safe relay in ABS (ABS/TCS) HU/CM stuck ON when ignition key 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 circuit or short of fail-safe relay in ABS (ABS/TCS) HU/CM
• Stuck fail-safe relay in ABS (ABS/TCS) HU/CM

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT ABS FUSE CONDITION
• Is ABS fuse (60 A) normal?
Yes
Go to the next step.
No
Replace fuse, then go to Step 4.
2
INSPECT FAIL-SAFE RELAY POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
• Turn the ignition switch off.
• Disconnect ABS (ABS/TCS) HU/CM connector.
• Turn the ignition switch to the ON position (engine off).
• Measure voltage between ABS (ABS/TCS) HU/CM terminal AA (harness-side) and ground.
• Is voltage B+?
Yes
Go to the next step.
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 the ignition switch off.
• Connect WDS or equivalent to DLC-2.
• Turn the ignition switch to the ON position (engine off).
• Access ABS_VOLT using the WDS or equivalent.
• Does fail-safe relay operate?
Yes
Go to the next step.
No
Replace ABS (ABS/TCS) HU/CM, then go to the next step.
4
VERIFY TROUBLESHOOTING COMPLETED
• Clear the DTC from the memory.
• Is same DTC present?
Yes
Replace ABS (ABS/TCS) HU/CM, then go to the next step.
No
Go to the next step.
5
VERIFY AFTER REPAIR PROCEDURE
• Is there any other DTC present?
Yes
Go to the applicable DTC inspection.
(See DTC Table.)
No
Troubleshooting completed.