Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Left Low Beam Fan Malfunction (B243D,B243E)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System(for Gasoline Model With Cornering Light) / Left Low Beam Fan Malfunction (B243D,B243E)

DESCRIPTION

The headlight ECU sub-assembly operates the low beam fan to cool the headlight LED unit in order to prevent the headlight LED unit from overheating.

Illuminates the low beam headlights and continuously operates the low beam fan.

The headlight ECU sub-assembly monitors the pulse signals from the FANP terminal when the low beam fans are operating.

HINT:

If B243D or B243E is output, the headlight ECU sub-assembly performs low beam headlight dimming control.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B243D

Left Low Beam Fan Malfunction
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
  • Fan speed signals from the low beam fan of less than 2550 rpm are continuously detected
  • 4 seconds or more
  • Headlight ECU sub-assembly LH
  • Headlight assembly LH

Headlight ECU sub-assembly LH

B243E

Right Low Beam Fan Malfunction
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
  • Fan speed signals from the low beam fan of less than 2550 rpm are continuously detected
  • 4 seconds or more
  • Headlight ECU sub-assembly RH
  • Headlight assembly RH

Headlight ECU sub-assembly RH

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.

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 or HL AutoLeveling (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs Body Electrical > HL AutoLeveling (Sub) > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

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

(c) Operate the light control switch to turn on the low beam headlights and wait 4 seconds or more.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / HL AutoLeveling or HL AutoLeveling (Sub) / Trouble Codes.

(f) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes Body Electrical > HL AutoLeveling (Sub) > Trouble Codes

OK:

DTC B243D and B243E are not output.

Result

Proceed to

OK

A

NG (DTC B243D is output)

B

NG (DTC B243E is output)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 6

B

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.

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 or HL AutoLeveling (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs Body Electrical > HL AutoLeveling (Sub) > Clear DTCs
NEXT

5.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

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

(c) Operate the light control switch to turn on the low beam headlights and wait 4 seconds or more.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / HL AutoLeveling or HL AutoLeveling (Sub) / Trouble Codes.

(f) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes Body Electrical > HL AutoLeveling (Sub) > Trouble Codes

Result

Proceed to

DTC B243D is output

A

DTC B243E is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

B

REPLACE HEADLIGHT ASSEMBLY LH

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.

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 or HL AutoLeveling (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs Body Electrical > HL AutoLeveling (Sub) > Clear DTCs
NEXT

8.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

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

(c) Operate the light control switch to turn on the low beam headlights and wait 4 seconds or more.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / HL AutoLeveling or HL AutoLeveling (Sub) / Trouble Codes.

(f) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes Body Electrical > HL AutoLeveling (Sub) > Trouble Codes

Result

Proceed to

DTC B243E is output

A

DTC B243D is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

B

REPLACE HEADLIGHT ASSEMBLY RH

    Open in B Power Line (B242F)

    Light Sensor Circuit (B1244)

    See More:

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    Toyota Avalon (XX50) 2019-2022 Owners Manual

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

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