Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM1000000018K3J
Model Year Start: 2018 Model: Sienna Prod Date Range: [11/2017 -           ]
Title: CRUISE CONTROL: LANE DEPARTURE ALERT SYSTEM(w/ Steering Control): C1A72; Communication Error from FCM to Driving Support ECU; 2018 - 2020 MY Sienna [11/2017 -        ]

DTC

C1A72

Communication Error from FCM to Driving Support ECU

DESCRIPTION

If a communication error between the driving support ECU assembly and forward recognition camera is detected, DTC C1A72 is stored.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1A72

Communication Error from FCM to Driving Support ECU

2 seconds after the ignition switch is turned to ON, a communication error between the driving support ECU assembly and the forward recognition camera is detected.

  • CAN communication system
  • Forward recognition camera
  • Driving support ECU assembly

CAUTION / NOTICE / HINT

NOTICE:

  • When replacing the forward recognition camera, always replace it with a new one. If a forward recognition camera which was installed to another vehicle is used, the information stored in the forward recognition camera will not match the information from the vehicle. As a result, a DTC may be stored.
  • If the forward recognition camera has been replaced with a new one, be sure to perform forward recognition camera adjustment.

    Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: FRONT CAMERA: ADJUSTMENT (SEQUENTIAL RECOGNITION)

  • When replacing the driving support ECU assembly, always replace it with a new one. If a driving support ECU assembly which was installed to another vehicle is used, the information stored in the driving support ECU assembly will not match the information from the vehicle. As a result, a DTC may be stored.
  • The lane departure alert system uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.

    Click here 2018 - 2020 MY Sienna [11/2017 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

PROCEDURE

1.

CHECK FOR DTCs (PRE-COLLISION SYSTEM)

HINT:

Confirm that there is no communication error between the forward recognition camera and driving support ECU assembly.

(a) Check for DTCs are output.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; PRE-COLLISION: PRE-COLLISION SYSTEM: DTC CHECK / CLEAR

Result

Proceed to

DTC U023A is not output

A

DTC U023A is output

B

B

GO TO PRE-COLLISION SYSTEM

A

2.

CHECK FOR DTCs (LANE DEPARTURE ALERT SYSTEM)

(a) Clear the DTCs.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: LANE DEPARTURE ALERT SYSTEM(w/ Steering Control): DTC CHECK / CLEAR

(b) Perform the following procedure.

HINT:

If the following procedure is not performed, the previously output DTC cannot be detected.

  1. Turn the ignition switch to ON and wait 7 seconds or more.

(c) Check for DTCs.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: LANE DEPARTURE ALERT SYSTEM(w/ Steering Control): DTC CHECK / CLEAR

Result

Proceed to

DTC C1A72 is not output

A

DTC C1A72 is output

B

A

USE SIMULATION METHOD TO CHECK

B

3.

REPLACE FORWARD RECOGNITION CAMERA

(a) Replace the forward recognition camera.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: FRONT CAMERA: REMOVAL

(b) Perform forward recognition camera adjustment.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: FRONT CAMERA: ADJUSTMENT (SEQUENTIAL RECOGNITION)

NEXT

4.

CHECK FOR DTCs (LANE DEPARTURE ALERT SYSTEM)

(a) Clear the DTCs.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: LANE DEPARTURE ALERT SYSTEM(w/ Steering Control): DTC CHECK / CLEAR

(b) Perform the following procedure.

HINT:

If the following procedure is not performed, the previously output DTC cannot be detected.

  1. Turn the ignition switch to ON and wait 7 seconds or more.

(c) Check for DTCs.

Click here 2018 - 2020 MY Sienna [11/2017 -        ]; CRUISE CONTROL: LANE DEPARTURE ALERT SYSTEM(w/ Steering Control): DTC CHECK / CLEAR

Result

Proceed to

DTC C1A72 is not output

A

DTC C1A72 is output

B

A

END (FORWARD RECOGNITION CAMERA WAS DEFECTIVE)

B

REPLACE DRIVING SUPPORT ECU ASSEMBLY