LIGHTING SYSTEM High Beam Headlight Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the high beam headlights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK OPERATION (LOW BEAM HEADLIGHTS)

   
   

   1. Check the operation of the low beam headlights.

      OK
      Low beam headlights operate normally.

   
   

   NG

   GO TO PROBLEM SYMPTOMS TABLE Click here

   OK

2. PERFORM ACTIVE TEST USING GTS

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Main Body / Active Test.

   5. Check that the high beam headlights illuminate.

      Main Body

      Tester Display	Test Part	Control Range	Diagnostic Note
      Head Light Hi	High beam headlights	ON/OFF	-

      OK
      High beam headlights illuminate.

   
   

   OK

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

   NG

3. INSPECT HEADLIGHT DIMMER RELAY (DIM)

   
   

   1. 

      Remove the DIM relay from the engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3 - 5 Voltage is not applied between terminals 1 and 2 10 kΩ or higher 3 - 5 Voltage is applied between terminals 1 and 2 Below 1 Ω

   
   

   NG

   REPLACE HEADLIGHT DIMMER RELAY

   OK

4. CHECK HARNESS AND CONNECTOR (H-LP HI MAIN FUSE - HEADLIGHT DIMMER RELAY)

   
   

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

      Standard Voltage
      Tester Connection Condition Specified Condition Relay terminal 2 - Body ground Power switch off 11 to 14 V Relay terminal 3 - Body ground Power switch off 11 to 14 V

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

   
   

   1. Disconnect the 2C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Relay terminal 1 - 2C-22 Always Below 1 Ω 2C-22 - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

6. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER RELAY - HEADLIGHT ASSEMBLY AND BODY GROUND)

   
   

   1. Disconnect the A84*1 or A78*2 headlight assembly LH connector and the A86*1 or A83*2 headlight assembly RH connector.

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

      Standard Resistance
      LH Side Tester Connection Condition Specified Condition Relay terminal 5 - A84-2 (HI)*1 Always Below 1 Ω Relay terminal 5 - A78-2 (HI)*2 Always Below 1 Ω A84-2 (HI)*1 - Body ground Always 10 kΩ or higher A78-2 (HI)*2 - Body ground Always 10 kΩ or higher A84-5 (E)*1 - Body ground Always Below 1 Ω A78-1 (E)*2 - Body ground Always Below 1 Ω
      RH Side Tester Connection Condition Specified Condition Relay terminal 5 - A86-2 (HI)*1 Always Below 1 Ω Relay terminal 5 - A83-2 (HI)*2 Always Below 1 Ω A86-2 (HI)*1 - Body ground Always 10 kΩ or higher A83-2 (HI)*2 - Body ground Always 10 kΩ or higher A86-5 (E)*1 - Body ground Always Below 1 Ω A83-1 (E)*2 - Body ground Always Below 1 Ω

      
      

      • *1: for LED Headlight

      • *2: for Halogen Headlight

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

7. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

   
   
   1. 

      Text in Illustration

      *a	Component without harness connected (Instrument Panel Junction Block Assembly)

      Remove the instrument panel junction block assembly Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition 2C-22 - MB-22 (DIM) Always Below 1 Ω 2C-22 - Body ground Always 10 kΩ or higher

   
   

   OK

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

   NG

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here