Code No. C1784: FCM switch fixed ON


caution If a diagnosis code is set, be sure to diagnose the CAN bus line.

DIAGNOSTIC FUNCTION


If the laser radar detects that the FCM-LS and RMS (Forward) OFF switch has been on for one minute or more, diagnosis code No. C1784 is set.

CHECK CONDITION


When all the following conditions are satisfied

PROBABLE CAUSES



DIAGNOSIS PROCEDURE


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


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

Q. Is the check result normal?

Go to Step 2.

Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ).

STEP 2. M.U.T.-III other system data list


Check the ASC-ECU service data (Refer to GROUP 35C - Troubleshooting ).

Q. Is the check result normal?

Go to Step 6.

Go to Step 3.

STEP 3. FCM-LS and RMS (Forward) OFF switch check


Check the FCM-LS and RMS (Forward) OFF switch (Refer to ).

Q. Is the check result normal?

Go to Step 4.

Replace the FCM-LS and RMS (Forward) OFF switch.

STEP 4. Check of short to earth in the FCSW line between the switch connector of the FCM-LS and RMS (Forward) OFF switch and the ASC-ECU connector.


Q. Is the check result normal?

Go to Step 5.

Repair the connector(s) or wiring harness.

STEP 5. M.U.T.-III other system data list


Check the ASC-ECU service data (Refer to GROUP 35C - Troubleshooting ).

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the ASC-ECU (Refer to GROUP 35C - Hydraulic Unit ).

STEP 6. M.U.T.-III data list


Check the service data of the laser radar (Refer to ).

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the laser radar (Refer to ).