PRE-COLLISION: PRE-COLLISION SYSTEM (for HV Model): U023A87; Lost Communication with Image Processing Module "A" Missing Message; 2020 - 2022 MY Corolla Corolla HV [01/2019

Last Modified: 05-13-2024	6.11:8.1.0	Doc ID: RM100000001G4E5
Model Year Start: 2020	Model: Corolla	Prod Date Range: [01/2019 - 09/2022]
Title: PRE-COLLISION: PRE-COLLISION SYSTEM (for HV Model): U023A87; Lost Communication with Image Processing Module "A" Missing Message; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

DTC

U023A87

Lost Communication with Image Processing Module "A" Missing Message

DESCRIPTION

The forward recognition camera communicates with the skid control ECU (brake booster with master cylinder assembly) via CAN communication.

If a communication error is detected between the skid control ECU (brake booster with master cylinder assembly) and forward recognition camera, the forward recognition camera stores this DTC.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
U023A87	Lost Communication with Image Processing Module "A" Missing Message	When the power switch is on (IG) for 2 seconds or more, a communication malfunction between the skid control ECU (brake booster with master cylinder assembly) the forward recognition camera is detected for 3 seconds or more.	Electronically controlled brake system Forward recognition camera

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 and a DTC may be stored.
If the forward recognition camera has been replaced with a new one, forward recognition camera adjustment must be performed.
HINT:

Forward recognition camera adjustment can be performed by using either One Time Recognition or Sequential Recognition.

One Time Recognition: Click here

Sequential Recognition: Click here

PROCEDURE

1.	CHECK FOR DTCs

(a) Using the Techstream, check for electronically controlled brake system DTCs.

Chassis > ABS/VSC/TRAC > Trouble Codes

HINT:

If DTC U023A87 and electronically controlled brake system DTCs are output, perform troubleshooting for the electronically controlled brake system first.

Result	Proceed to
Electronically controlled brake system DTCs are not output	A
Electronically controlled brake system DTCs are output	B

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM

2.	TEST MODE INSPECTION (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)

HINT:

When entering Test Mode (Signal Check), the skid control ECU (brake booster with master cylinder assembly) communicates with the forward recognition camera to judge whether the vehicle is equipped with the pre-collision system. Therefore, do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check).

(a) Procedure to Enter Test Mode (Signal Check)

(1) Turn the power switch off.

(2) Check that the steering wheel is centered.

(3) Check that the shift lever is in P.

(4) Connect the Techstream to the DLC3.

(5) Turn the power switch on (IG).

(6) Turn the Techstream on.

(7) Switch the skid control ECU (brake booster with master cylinder assembly) to Test Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / ABS/VSC/TRAC / Utility / Signal Check.

Chassis > ABS/VSC/TRAC > Utility

Tester Display
Signal Check

HINT:

Do not exit Test Mode (Signal Check) within 5 seconds of entering Test Mode (Signal Check). If Test Mode (Signal Check) is exited within 5 seconds of entering Test Mode (Signal Check), DTC U023A87 may be stored. If DTC U023A87 is output after exiting Test Mode (Signal Check), enter Test Mode (Signal Check) again, wait at least 5 seconds, then recheck for DTCs.

(b) Test Mode (Signal Check) Display Check

(1) Check that the ABS warning, brake warning / yellow (minor malfunction) and slip indicator lights come on for several seconds and then blink in the Test Mode pattern.

HINT:

If the ABS warning light, brake warning light / yellow (minor malfunction) or slip indicator light remains illuminated or does not illuminate when Test Mode (Signal Check) is entered, a component or wire harness may be malfunctioning.

(1) Turn the power switch off and disconnect the Techstream.

3.	CHECK FOR DTCs

(a) Clear the DTCs.

Body Electrical > Pre-Collision System > 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.

Body Electrical > Pre-Collision System > Trouble Codes

Result	Proceed to
DTC U023A87 is not output	A
DTC U023A87 is output	B

END

REPLACE FORWARD RECOGNITION CAMERA