DTC U023A-87: Lost Communication with Image Processing Module "A" Missing Message [10/2018 - 07/2022]: Procedure

CHECK FOR DTCs

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

for Gasoline Model:

Chassis > Brake/EPB > Trouble Codes

for HV Model:

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

Result	Proceed to
Electronically controlled brake system DTCs are not output (for Gasoline Model)	A
Electronically controlled brake system DTCs are not output (for HV Model)	B
Electronically controlled brake system DTCs are output (for Gasoline Model)	C
Electronically controlled brake system DTCs are output (for HV Model)	D

Result:

See step 4

Result:

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - 07/2022]

Result:

GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ]

Result:

See step 2

PERFORM DEALER MODE (SIGNAL CHECK) (ELECTRONICALLY CONTROLLED BRAKE SYSTEM)

HINT:

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

Procedure to enter Dealer Mode (Signal Check)

Turn the ignition switch off.
Apply the parking brake.
Check that the shift lever is in P.
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Check that the steering wheel is centered.
Turn the Techstream on.

Switch the skid control ECU (brake actuator assembly) to Dealer Mode (Signal Check) using the Techstream. Enter the following menus: Chassis / Brake/EPB / Utility / Signal Check.

Chassis > Brake/EPB > Utility

Tester Display
Signal Check

HINT:

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

Confirm the system has entered Dealer Mode (Signal Check).
1. Confirm that the ABS warning light and slip indicator light indicate the Dealer Mode pattern (blinking at 0.25 second intervals).
  HINT:
  - If the ABS warning light or slip indicator light remains illuminated or does not illuminate when Dealer Mode (Signal Check) is entered, a component or wire harness may be malfunctioning.
  - When entering Dealer Mode (Signal Check), if the parking brake is engaged, the parking brake indicator light (red) will illuminate, and if the parking brake is not engaged, the parking brake indicator light (red) will blink in the Dealer Mode pattern (blinking at 0.25 second intervals).

End of Dealer Mode (Signal Check)

Turn the ignition switch off.
Disconnect the Techstream.

Result

Proceed to
NEXT

Result:

See step 3

CHECK FOR DTCs

Clear the DTCs.
Body Electrical > Pre-Collision System > Clear DTCs
Make sure that the DTC detection conditions are met.
HINT:

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

Check for DTCs.

Body Electrical > Pre-Collision System > Trouble Codes

Result

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

Result:

END

Result:

REPLACE FORWARD RECOGNITION CAMERA. Refer to COMPONENTS [10/2018 - ]

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).

Procedure to Enter Test Mode (Signal Check)

Turn the ignition switch off.
Check that the steering wheel is centered.
Check that the shift lever is in P.
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.

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.

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.

End of Test Mode (Signal Check)

Turn the ignition switch off and disconnect the Techstream.

Result

Proceed to
NEXT

Result:

See step 5

CHECK FOR DTCs

Clear the DTCs.
Body Electrical > Pre-Collision System > Clear DTCs
Make sure that the DTC detection conditions are met.
HINT:

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

Check for DTCs.

Body Electrical > Pre-Collision System > Trouble Codes

Result

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

Result:

END

Result:

REPLACE FORWARD RECOGNITION CAMERA. Refer to COMPONENTS [10/2018 - ]