Inspection Procedure 2: The system cannot be activated or deactivated when you operate the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch.

COMMENTS ON TROUBLE SYMPTOM

When the system cannot be activated or deactivated by operating the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch, the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch, the CAN bas lines, the ASTC-ECU or the clearance warning control unit may have a problem.

PROBABLE CAUSES

Malfunction of CAN bas line
Malfunction of forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch
Malfunction of ASTC-ECU
Malfunction of clearance warning control unit
Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list.

Check the ASTC-ECU system data list (Refer to GROUP 35C - Data List Reference Table

Operate the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch.

Item No.	Item name	Normal condition
32	FCM off switch	When the switch is operated: ON When the switch is not operated: OFF

OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 6.

Go to Step 2.

STEP 2. Check of short to earth, and open circuit in power supply line between the ASTC-ECU connector and forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch connector.

Q. Is the check result normal?

Go to Step 3.

Repair the connector(s) or wiring harness.

STEP 3. Check of open circuit in earth line between the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch connector and body earth.

Q. Is the check result normal?

Go to Step 4.

Repair the connector(s) or wiring harness.

STEP 4. Check the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch.

Refer to

Q. Is the check result normal?

Go to Step 5.

Replace the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch (Refer to

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

Check the ASTC-ECU system data list (Refer to GROUP 35C - Data List Reference Table

Operate the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch.

Item No.	Item name	Normal condition
32	FCM off switch	When the switch is operated: ON When the switch is not operated: OFF

OK: Normal condition is displayed.

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 ASTC-ECU (Refer to GROUP 35C - FCM-ECU

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

Check the input signal (Refer to

Operate the forward collision mitigation system (FCM) and Ultrasonic misacceleration Mitigation System ON/OFF switch.

Item No.	Item name	Normal condition
18	FCM OFF SW input signal (CAN)	When the switch is operated: ON When the switch is not operated: OFF

OK: Normal condition is displayed.

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 clearance warning control unit (Refer to