LIGHTING SYSTEM Low Beam Headlight Circuit

DESCRIPTION

The main body ECU controls the low beam headlights via the H-LP/US-DRL relay.

CAUTION / NOTICE / HINT

PROCEDURE

1. Click here

   PERFORM ACTIVE TEST USING INTELLIGENT TESTER (HEADLIGHT RELAY)

   
   

   1. Connect the intelligent tester to the DLC3.

   2. Turn the ignition switch to ON (IG).

   3. Turn the intelligent tester on.

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

   5. According to the display on the intelligent tester, perform the Active Test.

      Table 1. Main Body

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

      OK
      Headlight relay operates (Low beam headlights illuminate).

   
   
   • OK

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

   • NGClick here
2. Click here

   INSPECT HEADLIGHT RELAY (H-LP/US-DRL RELAY)

   
   

   1. Remove the headlight relay (H-LP/US-DRL relay).

   2. Inspect the headlight relay (H-LP/US-DRL relay) (Click here).

   
   
   • OKClick here
   • NG

     REPLACE HEADLIGHT RELAY (H-LP/US-DRL RELAY)

3. Click here

   CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY - BATTERY)

   
   
   1. 

      Remove the headlight relay (H-LP/US-DRL relay) from the No. 2 engine room relay block.

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

      Standard Voltage
      Tester Connection Condition Specified Condition H-LP/US-DRL-1 - Body ground Always 11 to 14 V H-LP/US-DRL-3 - Body ground Always 11 to 14 V

      Table 2. Text in Illustration

      *1	No. 2 Engine Room Relay Block
      *2	Headlight Relay (H-LP/US-DRL Relay) Holder

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

4. Click here

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

   
   

   1. Remove the headlight relay (H-LP/US-DRL relay) from the No. 2 engine room relay block.

   2. Disconnect the 3C instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition H-LP/US-DRL-2 - 3C-18 Always Below 1 Ω H-LP/US-DRL-2 or 3C-18 - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

5. Click here

   INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

   
   

   1. Remove the instrument panel junction block assembly.

   2. Remove the main body ECU from the instrument panel junction block assembly.

   3. 

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

      Table 3. Text in Illustration

      *a

      Component without harness connected (Instrument Panel Junction Block Assembly)

      -

      -

      Standard Resistance
      Tester Connection Condition Specified Condition 3C-18 - MB-15 (HRLY) Always Below 1 Ω

   
   
   • OK

     REPLACE MAIN BODY ECU (Click here)

   • NG

     REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY