Diagnosis Item 2: Malfunction of the ETACS-ECU


caution When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water pipe. If you fail to do, a component connected to the CAN bus line may be broken.

FUNCTION


When the CAN bus diagnosis is carried out, the M.U.T.-III sets communication "OK" flags in the patch between the ETACS-ECU and active other ECUs. If a commutation "OK" flag is not set for the ECUs other than the ETACS-ECU, this diagnosis result will be set.

TRUBLE JUDGEMENT CONDITIONS


If no communication flags are set for the ECUs (on the CAN-B or CAN-C lines) other than the ETACS-ECU, the ETACS-ECU determines that there is a failure.

TROUBLESHOOTING HINTS



DIAGNOSIS PROCEDURE

M.U.T.-III other system diagnosis code
Check whether ETACS-ECU-related diagnosis code is set.

Q. Is the diagnosis code set?
The diagnosis code other than the U code is set. : Troubleshoot the ETACS-ECU. Refer to GROUP 54A - ETACS-ECU .
Only U-code diagnosis code is set. : Check the power supply circuit of the ETACS-ECU. Refer to GROUP 54A - ETACS-ECU .
The diagnosis code is not set. : Check the power supply circuit of the ETACS-ECU. Refer to GROUP 54A - ETACS-ECU .