Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: High Beam Headlight Circuit

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System(for Gasoline Model With Cornering Light) / High Beam Headlight Circuit

DESCRIPTION

The headlight ECU sub-assembly controls the high beam headlights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information the headlight ECU sub-assembly LH.

    Click here

  • If the headlight assembly LH has been replaced, it is necessary to synchronize the vehicle information the headlight ECU sub-assembly LH.

    Click here

PROCEDURE

1.

CHECK LIGHTS

(a) Check the illumination of each high beam lights.

Result

Proceed to

LH side high beam light does not illuminate

A

RH side high beam light does not illuminate

B
B

GO TO STEP 5

A

2.

PERFORM ACTIVE TEST USING TECHSTREAM

(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 / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > HL AutoLeveling > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Headlight High Beam

High beam headlights

OFF or ON

-
Body Electrical > HL AutoLeveling > Active Test

Tester Display

Headlight High Beam

OK:

High beam headlight turn on.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

3.

CHECK HEADLIGHT ASSEMBLY LH

(a) Remove each headlight ECU sub-assembly, interchange the headlight assembly LH with RH and connect the connectors.

Click here

NEXT

4.

CHECK OPERATION (HIGH BEAM HEADLIGHT)

(a) Check that the high beam headlight operates normally.

OK:

High beam headlight operates normally.

OK

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

NG

REPLACE HEADLIGHT ASSEMBLY LH

5.

PERFORM ACTIVE TEST USING TECHSTREAM

(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 (Sub) / Active Test.

(e) Perform the Active Test according to the display on the Techstream.

Body Electrical > HL AutoLeveling (Sub) > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Headlight High Beam

High beam headlights

OFF or ON

-
Body Electrical > HL AutoLeveling (Sub) > Active Test

Tester Display

Headlight High Beam

OK:

High beam headlight turn on.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

6.

CHECK HEADLIGHT ASSEMBLY RH

(a) Remove each headlight ECU sub-assembly, interchange the headlight assembly RH with LH and connect the connectors.

Click here

NEXT

7.

CHECK OPERATION (HIGH BEAM HEADLIGHT)

(a) Check that the high beam headlight operates normally.

OK:

High beam headlight operates normally.

OK

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

NG

REPLACE HEADLIGHT ASSEMBLY RH

    Headlight Dimmer Switch Circuit

    How To Proceed With Troubleshooting

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    Toyota Avalon (XX50) 2019-2022 Owners Manual

    Toyota Avalon (XX50) 2019-2022 Service & Repair Manual

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