Inspection Procedure 20: The FCM is cancelled in conjunction with a warning message while the FCM is activated.

caution

If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).
Before replacing the ECU, ensure that the communication circuit is normal.

COMMENTS ON TROUBLE SYMPTOM

The ACC/FCM-ECU has detected FCM control cancel signal.
A malfunction may be present in the CAN bus line between the ACC/FCM-ECU and the ASC-ECU or the ASC-ECU itself.

PROBABLE CAUSES

Wiring harness or connector failure of CAN bus line
Malfunction of ASC system
Malfunction of ACC/FCM-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics

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

Q. Is the check result normal?

	Go to Step 2

	Repair the CAN bus lines (Refer to GROUP 54C - CAN Bus Diagnostics Table ).

STEP 2. M.U.T.-III Diagnosis code of other system

Use M.U.T.-III to check that the diagnosis code is set by the ACC/FCM-ECU.

Q. Is the diagnosis code set?

	Troubleshoot for the relevant diagnosis code (Refer to GROUP 17 - Adaptive Cruise Control System (ACC) ).

	Go to Step 3

STEP 3. M.U.T.-III diagnosis code

Use M.U.T.-III to check the diagnosis code for the ASC system (Refer to

).

Q. Is the diagnosis code set?

	Carry out the diagnosis for the diagnosis code (Refer to ).

	Go to Step 4

STEP 4. Retest the system.

Check that the FCM control operates normally.

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).

	Replace the ACC/FCM-ECU (Refer to GROUP 17 - Adaptive Cruise Control System (ACC) ).