Lexus ES: Right Headlight ECU Malfunction (B242C,B242D)
DESCRIPTION
The headlight ECU sub-assembly LH or headlight ECU sub-assembly RH stores a DTC if it detects an internal malfunction.
for LED Type Turn Signal Light| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
|---|---|---|---|---|
| B242C | Right Headlight ECU Malfunction |
| Headlight ECU sub-assembly RH | AFS (Sub) |
| B242D | Left Headlight ECU Malfunction |
| Headlight ECU sub-assembly LH | AFS |
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | DTC Output from |
|---|---|---|---|---|
| B242C | Right Headlight ECU Malfunction |
| Headlight ECU sub-assembly RH | HL AutoLeveling (Sub) |
| B242D | Left Headlight ECU Malfunction |
| Headlight ECU sub-assembly LH | HL AutoLeveling |
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
.gif)
-
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
-
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
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 | .gif) | GO TO STEP 4 |
|
.gif)
| 2. | CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power 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
|
| 3. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Wait for at least maximum 15 minutes.
(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 CodesOK:
DTC B242C and B242D are not output.
| Result | Proceed to |
|---|---|
| OK | A |
| NG (DTC B242C is output) | B |
| NG (DTC B242D is output) | C |
| A | | USE SIMULATION METHOD TO CHECK |
| B | | REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH |
| C | | REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH |
| 4. | CLEAR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power 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
|
| 5. | CHECK FOR DTC |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Wait for at least maximum 15 minutes.
(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 CodesOK:
DTC B242C and B242D are not output.
| Result | Proceed to |
|---|---|
| OK | A |
| NG (DTC B242C is output) | B |
| NG (DTC B242D is output) | C |
| A | | USE SIMULATION METHOD TO CHECK |
| B | | REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH |
| C | | REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH |
READ NEXT:
Open in IG Circuit (B242E)
DESCRIPTION The headlight ECU sub-assembly operates using the power source voltage input from the IG terminal and ECUB terminal. The IG terminal power source voltage is supplied by turning the IG1-NO.
Open in B Power Line (B242F)
DESCRIPTION The headlight ECU sub-assembly operates using the power source voltage input from the IG terminal and ECUB terminal. The power source voltage of the ECUB terminal is supplied when the main
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 respecti
SEE MORE:
Screen Flicker or Color Distortion
PROCEDURE 1. CHECK DISPLAY SETTING (a) Reset display settings (contrast, brightness) and check that the screen appears normal. OK: The display returns to normal. OK END (DISPLAY SETTING WAS CAUSE OF MALFUNCTION) NG PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TA
Reassembly
REASSEMBLY PROCEDURE 1. INSTALL REAR BUMPER REINFORCEMENT (a) Install the rear bumper reinforcement with the 6 bolts. Torque: 35 N·m {357 kgf·cm, 26 ft·lbf} 2. INSTALL REAR BUMPER PROTECTOR INSERT LH (a) Engage the guide and claw to install the rear bumper protector insert LH.
