Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual: CAN Communication Failure (Message Registry) (U1000)

Lexus RX (RX 350L, RX450h) 2016-2025 Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System (w/ Automatic Headlight Beam Level Control System) / CAN Communication Failure (Message Registry) (U1000)

DESCRIPTION

The No. 1 headlight ECU sub-assembly LH stores this DTC if it detects an internal malfunction related to the CAN communication system.

for Multiple Beam Headlight

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

U1000

CAN Communication Failure (Message Registry)
  • The engine switch is on (IG).
  • CAN communication failure
  • -

No. 1 headlight ECU sub-assembly LH

AFS
for Single Beam Headlight

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

U1000

CAN Communication Failure (Message Registry)
  • The engine switch is on (IG).
  • CAN communication failure
  • -

No. 1 headlight ECU sub-assembly LH

HL AutoLeveling

CAUTION / NOTICE / HINT

NOTICE:

  • If the No. 1 headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the No. 1 headlight ECU sub-assembly LH.

    Click here

  • If the headlight assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the No. 1 headlight ECU sub-assembly LH.*

    Click here

  • When replacing the No. 1 headlight ECU sub-assembly LH, always replace it with a new one. If a No. 1 headlight ECU sub-assembly LH which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.
  • When replacing the headlight assembly LH, always replace it with a new one. If a headlight assembly LH which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.*
    • *: for TMMC Made

PROCEDURE

1.

CONFIRM MODEL

(a) Choose the model to be inspected.

Result

Proceed to

for Multiple Beam Headlight

A

for Single Beam Headlight

B
B

GO TO STEP 4

A

2.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > AFS > Clear DTCs
NEXT

3.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / AFS / Trouble Codes.

(e) Check for DTCs.

Body Electrical > AFS > Trouble Codes

OK:

DTC U1000 is not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH

4.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs
NEXT

5.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / HL AutoLeveling / Trouble Codes.

(e) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes

OK:

DTC U1000 is not output.

OK

USE SIMULATION METHOD TO CHECK

NG

REPLACE NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH

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