LIGHTING SYSTEM, Diagnostic DTC:B2439, B243A

DTC Code DTC Name
B2439 Headlamp LH Circuit
B243A Headlamp RH Circuit

DESCRIPTION

This DTC is output when the light failure indicator sensor detects a LO beam malfunction and outputs a malfunction signal to the AFS ECU via the headlight shade ECU.

DTC Code DTC Detection Condition Trouble Area
B2439 Malfunction in headlight assembly LH (light source)

  • Headlight assembly LH

  • Headlight shade ECU

  • AFS ECU

  • Harness or connector
B243A Malfunction in headlight assembly RH (light source)

  • Headlight assembly RH

  • Headlight shade ECU

  • AFS ECU

  • Harness or connector

WIRING DIAGRAM

A01GL5IE03

INSPECTION PROCEDURE

Note

Check if DTC B2440 or B2441 is output. If output, refer to the following procedures Click here.

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTC Click here.


    NEXT

  2. CHECK HEADLIGHT ASSEMBLY (OPERATION)


    1. Check that the low beam headlights turns on normally when the headlight dimmer switch is operated.

      OK
      The low beam headlights turns on normally.

    NG

    PROCEED TO "LO-beam Headlight does not Illuminate" Click here

    OK

  3. CHECK FOR DTC


    1. Turn the engine switch on (IG).

    2. Turn on the low beam headlight by operating the headlight dimmer switch.

    3. Check for DTC Click here.

      OK
      DTC B2439 or B243A output does not occur

    NG

    CHECK HEADLIGHT SHADE ECU Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  4. CHECK HEADLIGHT SHADE ECU


    1. Temporarily replace the headlight shade ECU with a new or normally functioning one Click here.

    2. Turn the engine switch on (IG).

    3. Turn on the low beam headlight by operating the headlight dimmer switch.

    4. Check for DTC Click here.

      OK
      DTC B2439 or B243A output does not occur

    NG

    CHECK HEADLIGHT ASSEMBLY Click here

    OK

    END (HEADLIGHT SHADE ECU WAS DEFECTIVE)

  5. CHECK HEADLIGHT ASSEMBLY


    1. Temporarily replace the headlight with a new or normally functioning one Click here.

    2. Turn the engine switch on (IG).

    3. Turn on the high beam headlight by operating the headlight dimmer switch.

    4. Check for DTC Click here.

      OK
      DTC B2439 or B243A output does not occur

    NG

    REPLACE AFS ECU Click here

    OK

    END (HEADLIGHT WAS DEFECTIVE)