DTC B243D: Left Low Beam Fan Malfunction; DTC B243E: Right Low Beam Fan Malfunction [09/2014 - 10/2018]: Procedure

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CLEAR DTC

Clear the DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Clear DTCs

Result

Proceed to
NEXT

Result:

See step 2

CHECK FOR DTC

Turn the engine switch on (IG).
Operate the light control switch to turn on the low beam headlights and wait 2 minutes.

Check for DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Trouble Codes

DTC B243D and B243E are not output.

Result

Result	Proceed to
OK	A
NG (DTC B243D is output)	B
NG (DTC B243E is output)	C

Result:

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [09/2014 - 10/2015] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - 11/2017] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018]

Result:

See step 6

Result:

See step 3

REPLACE HEADLIGHT UNIT ASSEMBLY LH (HEADLIGHT FAN LH)

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

Refer to DISASSEMBLY [09/2014 - 10/2018]

Result

Proceed to
NEXT

Result:

See step 4

CLEAR DTC

Clear the DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Clear DTCs

Result

Proceed to
NEXT

Result:

See step 5

CHECK FOR DTC

Turn the engine switch on (IG).
Operate the light control switch to turn on the low beam headlights and wait 2 minutes.

Check for DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Trouble Codes

DTC B243D is not output.

Result

Proceed to
OK
NG

Result:

END (HEADLIGHT UNIT ASSEMBLY LH (HEADLIGHT FAN LH) WAS DEFECTIVE)

Result:

REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY LH. Refer to REMOVAL [09/2014 - 10/2018]

REPLACE HEADLIGHT UNIT ASSEMBLY RH (HEADLIGHT FAN RH)

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

Refer to DISASSEMBLY [09/2014 - 10/2018]

Result

Proceed to
NEXT

Result:

See step 7

CLEAR DTC

Clear the DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Clear DTCs

Result

Proceed to
NEXT

Result:

See step 8

CHECK FOR DTC

Turn the engine switch on (IG).
Operate the light control switch to turn on the low beam headlights and wait 2 minutes.

Check for DTCs.

Refer to DTC CHECK / CLEAR [09/2014 - 10/2018]

Body Electrical > HL AutoLeveling > Trouble Codes

DTC B243E is not output.

Result

Proceed to
OK
NG

Result:

END (HEADLIGHT UNIT ASSEMBLY RH (HEADLIGHT FAN RH) WAS DEFECTIVE)

Result:

REPLACE HEADLIGHT LIGHT CONTROL ECU SUB-ASSEMBLY RH. Refer to REMOVAL [09/2014 - 10/2018]