DTC C1186

id040200876300

DTC
C1186
Fail-safe relay system
DETECTION CONDITION
•  ABS HU/CM internal valve relay remains OFF when valve relay ON is commanded.
•  ABS HU/CM internal valve relay remains ON (stuck) when valve relay OFF is commanded.
POSSIBLE CAUSE
•  ABS/SOL 20 A fuse malfunction
•  Open circuit or short to ground in the wiring harness between the battery and the ABS HU/CM terminal C
•  Open or short circuit in the ABS HU/CM internal valve relay, or stuck valve relay
•  Poor connection at connectors (female terminal)

Diagnostic procedure

STEP

INSPECTION

ACTION
1
INSPECT ABS FUSE CONDITION
•  Is the ABS/SOL 20 A fuse normal?
Yes
Go to the next step.
No
Replace the fuse, then go to Step 3.
2
INSPECT VALVE RELAY POWER SUPPLY FOR OPEN CIRCUIT
•  Turn the ignition switch or engine switch off.
•  Disconnect ABS HU/CM connector.
•  Turn the ignition switch or engine switch to the ON position (engine off).
•  Measure voltage between ABS HU/CM terminal C (harness-side) and ground.
•  Is voltage B+?
Yes
Go to the next step.
No
Repair or replace the wiring harness for open circuit between battery positive terminal and ABS HU/CM terminal C, then go to the next step.
3
VERIFY TROUBLESHOOTING COMPLETED
•  Clear the DTC from the memory.
•  Is the same DTC present?
Yes
Replace the ABS HU/CM, then go to next step.
(See ABS HU/CM REMOVAL/INSTALLATION.)
No
Go to the next step.
4
VERIFY AFTER REPAIR PROCEDURE
•  Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See ON-BOARD DIAGNOSIS.)
No
DTC troubleshooting completed.