LIGHTING SYSTEM Headlight Signal Circuit

DESCRIPTION

The main body ECU receives a headlight low switch information signal from the light control switch, and illuminates the headlight low beam.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. PERFORM ACTIVE TEST USING GTS (HEADLIGHT)

   
   

   1. Using the GTS, perform the Active Test Click here.

      Main Body

      Tester Display	Test Part	Control Range	Diagnostic Note
      Headlight Relay	Headlight	ON or OFF	-

      OK
      Headlight low beam turns on/turns off.

   
   

   OK

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

   NG

2. INSPECT HEADLIGHT RELAY (H-LP LO OR H-LP LH)

   
   

   1. Inspect the headlight relay Click here.

   
   

   NG

   REPLACE HEADLIGHT RELAY (H-LP LO OR H-LP LH)

   OK

3. CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT RELAY [H-LP LO OR H-LP LH])

   
   
   1. 

      Text in Illustration

      *a	Front view of wire harness connector (to Headlight Relay [H-LP LO or H-LP LH])

      Remove the headlight relay from the engine room relay block, junction block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition Headlight relay terminal 1 - Body ground Always 11 to 14 V Headlight relay terminal 3 - Body ground

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP LO OR H-LP LH] - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU])

   
   

   1. Remove the headlight relay from the engine room relay block, junction block.

   2. Disconnect the 2H cowl side junction block LH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Headlight relay terminal 2 - 2H-30 Always Below 1 Ω Headlight relay terminal 2 - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. INSPECT COWL SIDE JUNCTION BLOCK LH

   
   

   1. for LHD:

      
      

      1. Remove the cowl side junction block LH Click here.

      2. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH Click here.

   2. 

      for RHD:

      
      

      1. Remove the cowl side junction block LH Click here.

      2. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition A-15 (HRLY) - 2H-30 Always Below 1 Ω

      Result

      Result	Proceed to
      OK (for LHD)	A
      NG (for LHD)	B
      NG (for RHD)	C
      OK (for RHD)	D

   
   

   A

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   B

   REPLACE COWL SIDE JUNCTION BLOCK LH Click here

   C

   REPLACE COWL SIDE JUNCTION BLOCK LH Click here

   D

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here