Inspection Procedure

If the M.U.T.-IIISE cannot diagnose the system properly, check the following items.

Symptom	Check item
M.U.T.-III SE cannot access any system.	M.U.T.-III SE DLC power supply circuit (Terminal 8 and 16) and ground circuit (Terminal 4 and 5) Check the power supply and ground circuit of 8CH CAN gateway. Refer to DIAGNOSIS PROCEDURE . Check the data link connector branch line circuit. Refer to DIAGNOSIS PROCEDURE . Check the diagnostic CAN communication circuit. Refer to DIAGNOSIS PROCEDURE . If above inspection results are normal, replace 8CH CAN gateway. Refer to DIAGNOSIS PROCEDURE .
M.U.T.-III SE cannot access individual system. (Other systems can be accessed.)	Power supply and ground circuit for the control unit of the system (For detailed circuit, refer to wiring diagram for each system.) Open or short circuit between the system and M.U.T.-III SE DLC (For detailed circuit, refer to wiring diagram for each system.) Open or short circuit CAN communication line. Refer to TROUBLE DIAGNOSIS FLOW CHART .

Symptom

Check item

M.U.T.-III SE cannot access any system.

M.U.T.-III SE DLC power supply circuit (Terminal 8 and 16) and ground circuit (Terminal 4 and 5)
Check the power supply and ground circuit of 8CH CAN gateway. Refer to DIAGNOSIS PROCEDURE .
Check the data link connector branch line circuit. Refer to DIAGNOSIS PROCEDURE .
Check the diagnostic CAN communication circuit. Refer to DIAGNOSIS PROCEDURE .
If above inspection results are normal, replace 8CH CAN gateway. Refer to DIAGNOSIS PROCEDURE .

M.U.T.-III SE cannot access individual system. (Other systems can be accessed.)

Power supply and ground circuit for the control unit of the system (For detailed circuit, refer to wiring diagram for each system.)
Open or short circuit between the system and M.U.T.-III SE DLC (For detailed circuit, refer to wiring diagram for each system.)
Open or short circuit CAN communication line. Refer to TROUBLE DIAGNOSIS FLOW CHART .

NOTE: The DDL1 and DDL2 circuits from DLC pins 12, 13, 14 and 15 may be connected to more than one system. A short in a DDL circuit connected to a control unit in one system may affect M.U.T.-III SE access to other systems.
If the GST cannot operate properly, check the circuit based on the information of SAE J1962 and ISO 15031-3.