Diagnostic Procedure

DTC C1139:64 (DSC HU/Control Module) DIAGNOSTIC PROCEDURE

Step	Inspection	Results	Action
1	ASK CUSTOMER IF AUTOHOLD SWITCH HAS BEEN PRESSED DOWN CONTINUOUSLY FOR 30 S OR MORE Ask the customer if the AUTOHOLD switch has been pressed down continuously for 30 s or more. Has the AUTOHOLD switch been pulled up/pressed down continuously for 30 s or more?	Yes	System is normal. (Explain to the customer that it is not necessary to continuously press down the AUTOHOLD switch to operate/release the AUTOHOLD system.)
1		No	Go to the next step.
2	DETERMINE MALFUNCTIONING LOCATION Perform the PID/data monitor inspection and display the following item. (See PID/DATA MONITOR INSPECTION .) (See PID/DATA MONITOR TABLE [ELECTRICAL SUPPLY UNIT (ESU) (US)] .) Electrical supply unit (ESU) AUTO_HOLD_SW Does the data monitor value change in conjunction with the AUTOHOLD switch operation?	Yes	Go to Step 7.
2		No	Go to the next step.
3	INSPECT ELECTRIC PARKING BRAKE SWITCH CONNECTOR FOR MALFUNCTION Inspect the applicable connector and terminal. (See CONNECTOR INSPECTION .) Are the connector and terminal normal?	Yes	Go to the next step.
3		No	Repair or replace the malfunctioning location and perform the repair completion verification.
4	VISUALLY INSPECT AUTOHOLD SWITCH FOR MALFUNCTION Visually verify the AUTOHOLD switch for the following. Interference with surrounding parts Foreign matter penetration in movable parts Is the AUTOHOLD switch normal?	Yes	Go to the next step.
4		No	Interference with surrounding parts: Install the electric parking brake switch correctly. (See ELECTRIC PARKING BRAKE SWITCH REMOVAL/INSTALLATION .) If the malfunction recurs, replace the electric parking brake switch. (See ELECTRIC PARKING BRAKE SWITCH REMOVAL/INSTALLATION .) Perform the repair completion verification. Foreign matter has penetrated movable parts: Remove the foreign matter and perform the repair completion verification.
5	INSPECT AUTOHOLD SWITCH FOR MALFUNCTION Inspect the applicable part. (See AUTO HOLD SWITCH INSPECTION .) Is the part normal?	Yes	Go to the next step.
5		No	Repair or replace the malfunctioning location and perform the repair completion verification. (See ELECTRIC PARKING BRAKE SWITCH REMOVAL/INSTALLATION .)
6	INSPECT AUTOHOLD SWITCH SIGNAL CIRCUIT FOR SHORT TO GROUND Inspect the applicable circuit for a short to ground. (See CIRCUIT INSPECTION .) Is the circuit normal?	Yes	Go to the next step.
6		No	Repair or replace the malfunctioning location and perform the repair completion verification.
7	INSPECT ELECTRICAL SUPPLY UNIT (ESU) FOR MALFUNCTION DEPENDING ON REPEATABILITY Install/connect the part removed/disconnected during the troubleshooting procedure. Clear the DTC recorded in the memory. (See CLEARING DTC .) Operate the AUTOHOLD switch 2 or 3 times, and then finally turn it off. Perform the DTC inspection for the DSC HU/Control Module. (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Refer to the CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(US)] .) If the CAN communication is normal, replace the malfunctioning location and perform the repair completion verification. (See ELECTRICAL SUPPLY UNIT (ESU) REMOVAL/INSTALLATION .)
7		No	Go to repair completion verification 2.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED Install/connect the part removed/disconnected during the troubleshooting procedure. Clear the DTC recorded in the memory. (See CLEARING DTC .) Operate the AUTOHOLD switch 2 or 3 times, and then finally turn it off. Perform the DTC inspection for the DSC HU/Control Module. (See DTC INSPECTION .) Is the same Pending DTC present?	Yes	Refer to the CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(US)] .) If the CAN communication is normal, perform the diagnosis from Step 1. If the malfunction recurs, replace the DSC HU/Control Module, then go to the next step. (See DSC HU/Control Module REMOVAL/INSTALLATION [L.H.D. (US)] .)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED Perform the DTC inspection. (See DTC INSPECTION .) Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.