AUTOMATIC HEADLIGHT BEAM LEVEL CONTROL SYSTEM Headlight Beam Level Control Actuator Circuit

DESCRIPTION

The headlight leveling ECU assembly actuates the headlight leveling motors according to vehicle conditions.

PROCEDURE

1. Click here

   PERFORM ACTIVE TEST USING GTS

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the power switch on (READY).

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / HL Auto Leveling / Active Test.

   5. Check that the leveling motors operate.

      Table 1. HL Auto Leveling

      Tester Display	Test Part	Control Range	Diagnostic Note
      Drive The Leveling Motor UP	Leveling motor upward operation	ON/OFF	ON: Moves up OFF: Stops
      Drive The Leveling Motor DOWN	Leveling motor downward operation	ON/OFF	ON: Moves down OFF: Stops

      OK
      Headlight leveling motors operate normally.

   
   
   • OK

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

   • NGClick here
2. Click here

   CHECK HARNESS AND CONNECTOR (HEADLIGHT ASSEMBLY - HEADLIGHT LEVELING ECU ASSEMBLY)

   
   

   1. Disconnect the A29 headlight leveling ECU assembly connector.

   2. Disconnect the A18 headlight assembly LH connector or A51 headlight assembly RH connector.

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

      Standard Resistance
      Table 2. for LH Side: Tester Connection Condition Specified Condition A29-18 (LHT) - A18-2 (LHT) Always Below 1 Ω A29-11 (LH+) - A18-3 (LHIG) Always Below 1 Ω A29-24 (LH-) - A18-6 (LHE) Always Below 1 Ω A29-18 (LHT) - Body ground Always 10 kΩ or higher A29-11 (LH+) - Body ground Always 10 kΩ or higher A29-24 (LH-) - Body ground Always 10 kΩ or higher
      Table 3. for RH Side: Tester Connection Condition Specified Condition A29-17 (RHT) - A51-2 (RHT) Always Below 1 Ω A29-10 (RH+) - A51-3 (RHIG) Always Below 1 Ω A29-23 (RH-) - A51-6 (RHE) Always Below 1 Ω A29-17 (RHT) - Body ground Always 10 kΩ or higher A29-10 (RH+) - Body ground Always 10 kΩ or higher A29-23 (RH-) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

3. Click here

   CHECK HEADLIGHT CORD

   
   

   1. Remove the headlight cord (Click here).

   2. for LH Side:

      
      
      1. 

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

         Standard Resistance
         Tester Connection Condition Specified Condition A18-3 (LHIG) - LVL-3 Always Below 1 Ω A18-2 (LHT) - LVL-2 Always Below 1 Ω A18-6 (LHE) - LVL-1 Always Below 1 Ω A18-3 (LHIG) - Body ground Always 10 kΩ or higher A18-2 (LHT) - Body ground Always 10 kΩ or higher A18-6 (LHE) - Body ground Always 10 kΩ or higher

         Table 4. Text in Illustration

         *a	Component without harness connected (Headlight Cord (for LH Side))

   3. for RH Side:

      
      
      1. 

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

         Standard Resistance
         Tester Connection Condition Specified Condition A51-3 (RHIG) - LVR-3 Always Below 1 Ω A51-2 (RHT) - LVR-2 Always Below 1 Ω A51-6 (RHE) - LVR-1 Always Below 1 Ω A51-3 (RHIG) - Body ground Always 10 kΩ or higher A51-2 (RHT) - Body ground Always 10 kΩ or higher A51-6 (RHE) - Body ground Always 10 kΩ or higher

         Table 5. Text in Illustration

         *a	Component without harness connected (Headlight Cord (for RH Side))

   
   
   • OKClick here
   • NG

     REPLACE HEADLIGHT CORD (Click here)

4. Click here

   CHECK HEADLIGHT LEVELING MOTOR

   
   

   1. Replace the headlight leveling motor with a new or known good one (Click here).

   2. Perform the active test of the leveling motors.

      OK
      Headlight leveling motors operate normally.

   
   
   • OK

     END (HEADLIGHT LEVELING MOTOR WAS DEFECTIVE)

   • NG

     REPLACE HEADLIGHT LEVELING ECU ASSEMBLY (Click here)