DTC C1A77:12/C1A77:13/C1A77:16 [ABS]

id0402a7880000

DTC
C1A77:12/C1A77:13/C1A77:16
Valve relay
DETECTION CONDITION
•  C1A77:12
―  Valve relay in ABS HU/CM stuck ON when switched the ignition to ON, valve relay OFF is commanded.
•  C1A77:13/C1A77:16
―  Valve relay in ABS HU/CM stuck OFF when valve relay ON is commanded.
POSSIBLE CAUSE
•  Malfunction of fuse (MAIN 125A, ABS MOTOR 60A or ABS SOL 30A)
•  Open circuit in harness between ABS HU/CM terminal AG and battery positive terminal
•  Open circuit or short of valve relay in ABS HU/CM
•  Stuck valve relay in ABS HU/CM

Diagnostic procedure

STEP

INSPECTION

ACTION
1
INSPECT ABS FUSE CONDITION
•  Is ABS fuse (MAIN 125A, ABS MOTOR 60A and ABS SOL 30A) normal?
Yes
Go to the next step.
No
Replace the fuse, then go to Step 3.
2
INSPECT VALVE RELAY POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT
•  Switch the ignition to off.
•  Disconnect ABS HU/CM connector.
•  Switch the ignition to ON (engine off).
•  Measure voltage between ABS HU/CM terminal AG (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 HU/CM terminal AG, then go to the next step.
3
VERIFY TROUBLESHOOTING COMPLETED
•  Reconnect all disconnected connectors.
•  Clear the DTC from the memory.
•  Is same DTC present?
Yes
Replace ABS HU/CM, then go to the next step.
(See ABS HU/CM REMOVAL/INSTALLATION.)
No
Go to the next step.
4
VERIFY AFTER REPAIR PROCEDURE
•  Is there any other DTC present?
Yes
Go to the applicable DTC inspection.
(See ON-BOARD DIAGNOSIS [ABS].)
No
Troubleshooting completed.