Toyota CH-R Service Manual: Headlamp LH Circuit (B2439,B243A)

Toyota CH-R Service Manual / Lighting (ext) / Lighting System / Headlamp LH Circuit (B2439,B243A)

DESCRIPTION

A DTC is stored when the headlight ECU sub-assembly receives a light source malfunction signal from its respective headlight unit. The headlight ECU sub-assembly LH stores DTC B2439 or B243A.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Note
B2439	Headlamp LH Circuit	headlight ECU sub-assembly LH light source malfunction	Headlight unit assembly LH Headlight ECU sub-assembly LH	-
B243A	Headlamp RH Circuit	headlight ECU sub-assembly RH light source malfunction	Headlight unit 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 and initialize the headlight ECU sub-assembly LH.

Click here

PROCEDURE

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > HL AutoLeveling > Clear DTCs

2.	CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights.

Click here

Body Electrical > HL AutoLeveling > 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

USE SIMULATION METHOD TO CHECK

GO TO STEP 6

3.	REPLACE HEADLIGHT UNIT ASSEMBLY LH

(a) Replace the headlight unit assembly LH with a new or known good one.

for Halogen Headlight: Click here
for LED Headlight: Click here

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > HL AutoLeveling > Clear DTCs

5.	CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights.

Click here

Body Electrical > HL AutoLeveling > Trouble Codes

OK:

DTC B2439 is not output.

END (HEADLIGHT UNIT ASSEMBLY LH WAS DEFECTIVE)

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

6.	REPLACE HEADLIGHT UNIT ASSEMBLY RH

(a) Replace the headlight unit assembly RH with a new or known good one.

for Halogen Headlight: Click here
for LED Headlight: Click here

CLEAR DTC

(a) Clear the DTCs.

Click here

Body Electrical > HL AutoLeveling > Clear DTCs

8.	CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Operate the light control switch to turn on the low beam headlights.

Click here

Body Electrical > HL AutoLeveling > Trouble Codes

OK:

DTC B243A is not output.

END (HEADLIGHT UNIT ASSEMBLY RH WAS DEFECTIVE)

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

Lost Communication With Headlamp Control Module "B" (U0242)

DESCRIPTION The headlight ECU sub-assembly LH stores this DTC when the headlight ECU sub-assembly RH detects an internal malfunction or if a communication malfunction occurs between headlight ECU ...

Right Headlight ECU Malfunction (B242C,B242D)

DESCRIPTION These DTCs are stored if the headlight ECU sub-assembly LH or RH detects an internal malfunction. The headlight ECU sub-assembly LH stores DTC B242C or B242D. DTC No. ...

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Toyota CH-R Service Manual: Headlamp LH Circuit (B2439,B243A)

Lost Communication With Headlamp Control Module "B" (U0242)

Right Headlight ECU Malfunction (B242C,B242D)

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