Lexus ES manuals

Lexus ES: Headlight LH Circuit (B2439,B243A)

Lexus ES (XZ10) Service Manual / Vehicle Exterior / Lighting (ext) / Lighting System (for Gasoline Model) / Headlight LH Circuit (B2439,B243A)

DESCRIPTION

The headlight ECU sub-assembly LH and headlight ECU sub-assembly RH internally boost the power supply voltage to ensure a constant supplied current for the lo/hi beam LED of their respective headlight.

By monitoring the LED power supply voltage, abnormal current and malfunctions can be detected.

for LED Type Turn Signal Light

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B2439

Headlight LH Circuit
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
Malfunction status:
  • Headlight unit assembly malfunction (for TMC Made)
  • Headlight assembly malfunction (for TMMK Made)
  • Open/short in Lo/Hi beam circuit
  • 10 seconds or more
  • Headlight ECU sub-assembly LH
  • Headlight unit assembly LH (for TMC Made)
  • Headlight assembly LH (for TMMK Made)

AFS

B243A

Headlight RH Circuit
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
Malfunction status:
  • Headlight unit assembly malfunction (for TMC Made)
  • Headlight assembly malfunction (for TMMK Made)
  • Open/short in Lo/Hi beam circuit
  • 10 seconds or more
  • Headlight ECU sub-assembly RH
  • Headlight unit assembly RH (for TMC Made)
  • Headlight assembly RH (for TMMK Made)

AFS (Sub)
for Bulb Type Turn Signal Light

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B2439

Headlight LH Circuit
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
Malfunction status:
  • Headlight unit assembly malfunction (for TMC Made)
  • Headlight assembly malfunction (for TMMK Made)
  • Open/short in Lo/Hi beam circuit
  • 10 seconds or more
  • Headlight ECU sub-assembly LH
  • Headlight unit assembly LH (for TMC Made)
  • Headlight assembly LH (for TMMK Made)

HL AutoLeveling

B243A

Headlight RH Circuit
  • All of the following conditions are met:
    • Engine switch on (IG)
    • Low beam headlights on
Malfunction status:
  • Headlight unit assembly malfunction (for TMC Made)
  • Headlight assembly malfunction (for TMMK Made)
  • Open/short in Lo/Hi beam circuit
  • 10 seconds or more
  • Headlight ECU sub-assembly RH
  • Headlight unit assembly RH (for TMC Made)
  • Headlight assembly RH (for TMMK Made)

HL AutoLeveling (Sub)

WIRING DIAGRAM

for LED Type Turn Signal Light

for Bulb Type Turn Signal Light (for TMC Made)

for Bulb Type Turn Signal Light (for TMMK Made)

CAUTION / NOTICE / HINT

NOTICE:

  • If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the headlight ECU sub-assembly LH.*1

    Click here

  • If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information the headlight ECU sub-assembly LH.*2

    Click here

  • If the headlight assembly LH has been replaced, it is necessary to synchronize the vehicle information the headlight ECU sub-assembly LH.*3

    Click here

  • When replacing the headlight ECU sub-assembly LH, always replace it with a new one. If a 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.
    • *1: for LED Type Turn Signal Light
    • *2: for Bulb Type Turn Signal Light
    • *3: for Bulb Type Turn Signal Light (for TMMK Made)

PROCEDURE

1.

CONFIRM MODEL

(a) Choose the model to be inspected.

Result

Proceed to

for LED Type Turn Signal Light

A

for Bulb Type Turn Signal Light

B
B

GO TO STEP 10

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 or AFS (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > AFS > Clear DTCs Body Electrical > AFS (Sub) > Clear DTCs
NEXT

3.

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 10 seconds or more.

(d) Turn the Techstream on.

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

(f) Check for DTCs.

Body Electrical > AFS > Trouble Codes Body Electrical > AFS (Sub) > Trouble Codes

OK:

DTC B2439 and B243A are not output.

Result

Proceed to

OK

A

NG (DTC B2439 is output)

B

NG (DTC B243A is output)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 7

B

4.

CHECK HEADLIGHT UNIT ASSEMBLY LH

(a) Interchange the headlight unit assembly LH with RH and connect the connectors.

Click here

NEXT

5.

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 or AFS (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > AFS > Clear DTCs Body Electrical > AFS (Sub) > Clear DTCs
NEXT

6.

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 10 seconds or more.

(d) Turn the Techstream on.

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

(f) Check for DTCs.

Body Electrical > AFS > Trouble Codes Body Electrical > AFS (Sub) > Trouble Codes

Result

Proceed to

DTC B2439 is output

A

DTC B243A is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

B

REPLACE HEADLIGHT UNIT ASSEMBLY LH

7.

CHECK HEADLIGHT UNIT ASSEMBLY RH

(a) Interchange the headlight unit assembly RH with LH and connect the connectors.

Click here

NEXT

8.

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 or AFS (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > AFS > Clear DTCs Body Electrical > AFS (Sub) > Clear DTCs
NEXT

9.

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 10 seconds or more.

(d) Turn the Techstream on.

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

(f) Check for DTCs.

Body Electrical > AFS > Trouble Codes Body Electrical > AFS (Sub) > Trouble Codes

Result

Proceed to

DTC B243A is output

A

DTC B2439 is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

B

REPLACE HEADLIGHT UNIT ASSEMBLY RH

10.

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

11.

CONFIRM MODEL

(a) Choose the model to be inspected.

Result

Proceed to

for TMC Made

A

for TMMK Made

B
B

GO TO STEP 19

A

12.

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 10 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 B2439 and B243A are not output.

Result

Proceed to

OK

A

NG (DTC B2439 is output)

B

NG (DTC B243A is output)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 16

B

13.

CHECK HEADLIGHT UNIT ASSEMBLY LH

(a) Interchange the headlight unit assembly LH with RH and connect the connectors.

Click here

NEXT

14.

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

15.

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 10 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 B2439 is output

A

DTC B243A is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

B

REPLACE HEADLIGHT UNIT ASSEMBLY LH

16.

CHECK HEADLIGHT UNIT ASSEMBLY RH

(a) Interchange the headlight unit assembly RH with LH and connect the connectors.

Click here

NEXT

17.

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

18.

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 10 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 B243A is output

A

DTC B2439 is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

B

REPLACE HEADLIGHT UNIT ASSEMBLY RH

19.

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 10 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 B2439 and B243A are not output.

Result

Proceed to

OK

A

NG (DTC B2439 is output)

B

NG (DTC B243A is output)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 23

B

20.

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

21.

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

22.

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 10 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 B2439 is output

A

DTC B243A is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

B

REPLACE HEADLIGHT ASSEMBLY LH

23.

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

24.

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

25.

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 10 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 B243A is output

A

DTC B2439 is output

B
A

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

B

REPLACE HEADLIGHT ASSEMBLY RH

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