Toyota Avalon Service & Repair Manual: Communication Error from FCM to Driving Support ECU (C1A72)

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 power switch is turned on (IG), a communication error between the driving support ECU assembly and the forward recognition camera is detected.	CAN communication system Forward recognition camera Pre-collision system

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.
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The lane departure alert system (w/ steering control) uses the CAN communication system. First, confirm that there are no malfunctions in the CAN communication system. Refer to How to Proceed with Troubleshooting.
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PROCEDURE

1.	CHECK FOR DTCs

HINT:

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

(a) Check for DTCs.

Body Electrical > Pre-Collision 2 > Trouble Codes

Result	Proceed to
DTC U023A is not output	A
DTC U023A is output	B

GO TO PRE-COLLISION SYSTEM

2.	CHECK FOR DTCs

(a) Clear the DTCs.

Chassis > LKA/LDA > Clear DTCs

(b) Make sure that the DTC detection conditions are met.

HINT:

If the detection conditions are not met, the system cannot detect the malfunction.

Chassis > LKA/LDA > Trouble Codes

Result	Proceed to
DTC C1A72 is not output	A
DTC C1A72 is output	B

USE SIMULATION METHOD TO CHECK

REPLACE FORWARD RECOGNITION CAMERA

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Toyota Avalon Owners Manual