INSPECTION PROCEDURE 1: Communication with the M.U.T.-III is not Possible.




COMMENTS ON TROUBLE SYMPTOM


If the system does not communicate with the M.U.T.-III, power supply to the diagnosis connector or CAN bus lines may be defective.

POSSIBLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Check that the engine-ECU communicates with the M.U.T.-III.
Check whether the DIESEL system-related diagnosis code is set.

Q. Is the check result satisfactory?
Go to Step 2.
Diagnose DIESEL system. (Refer to GROUP 13A, Troubleshooting .)

STEP 2. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result satisfactory?
Diagnose the power supply circuit. Refer to .
Repair the CAN bus lines (Refer to GROUP 54C, Diagnosis - Can Bus Diagnostics Table ).