DTC Troubleshooting

DTC TROUBLESHOOTING CHART

Step	Action	Value (s)	Yes	No
1	Perform an ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK . Is the system check complete?	-	Go to Step 2.	Go to ON-BOARD DIAGNOSTIC (OBD II) SYSTEM CHECK .
2	Turn the ignition OFF. Install a scan too to the Data Link Connector (DLC). Turn the ignition ON. Select IMMOBILIZER DIAGNOSIS STATUS from the scan tool menu. Is the communication established between the scan tool and the immobilizer control unit?	-	Go to Step 3.	Check immobilizer anti-theft system circuit. .
3	Turn the ignition OFF. Disconnect the Intelligent Switching Unit (ISU) and Engine Control Module (ECM) connectors. Measure the resistance between terminal A7 of ISU and terminal K76 of the ECM. Is the resistance within the specified value?	0 Ω	Go to Step 5.	Go to Step 4.
4	Repair an open circuit between terminal A7 of ISU and K76 the ECM. Is the repair complete?	-	Go to Step 8.	-
5	Check the terminals in ISU and the ECM for damages and repair as needed. Is the repair complete?	-	Go to Step 8.	Go to Step 6.
6	Replace the ISU. Is the repair complete?	-	Go to Step 8.	Go to Step 7.
7	Turn the ignition OFF. Replace the ECM. Is the repair complete?	-	Go to Step 8.	-
8	Using the scan tool, clear the Diagnostic Trouble Codes (DTCs). Start the engine and idle at normal operating temperature. Operate the vehicle within the Conditions for setting this DTC as specified in the supporting text. Does the scan tool indicate that this diagnostic has run and passed?	-	Go to Step 9.	Go to Step 2.
9	Check if any additional DTCs are set. Are any DTCs displayed that have not been diagnosed?	-	Go to applicable DTC Table .	System OK