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LIGHTING SYSTEM > Headlight Leveling ECU Power Source Circuit

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DESCRIPTION

This circuit detects the state of the power switch, and sends it to the headlight leveling ECU assembly.

WIRING DIAGRAM


E142597E22


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

1.READ VALUE USING INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body / HL Auto Leveling / Data List.

  1. Read the display on the intelligent tester.

    HL Auto Leveling 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    +B
    		IG power supply voltage value / 0 to 20 V
    		11 to 14 V
    		-

    OK:
    Normal condition listed above is displayed.



NG
Go to step 2
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Click here)  

2.CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT LEVELING ECU ASSEMBLY)


    E136327E32

  1. Disconnect the A48 headlight leveling ECU assembly connector.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A48-1 (IG) - Body ground
    		Power switch on (IG)
    		11 to 14 V
    A48-1 (IG) - Body ground
    		Power switch off
    		Below 1 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Headlight Leveling ECU assembly)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY - BODY GROUND)


    E136327E33

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A48-9 (E1) - Body ground
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Headlight Leveling ECU assembly)



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE HEADLIGHT LEVELING ECU ASSEMBLY (Click here)