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
After the ignition switch is turned ON, two or more seconds passed.
After the engine has started
PROBABLE CAUSES
Malfunction of the CAN bus line
Damaged harness or connector
Malfunction of the FCM-LS and RMS (Forward) OFF switch (ON stuck)
Malfunction of the ASC-ECU
Malfunction of the laser radar
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 ).
Item No.32: FCM-LS off switch
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 ).
Item No.32: FCM-LS off switch
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 ).
Item No.27: FCM-LS switch status
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 ).