LIGHTING SYSTEM Front Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the front fog lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK OPERATION (TAILLIGHTS)

   
   

   1. Check the operation of the taillights.

      OK
      Taillights operate normally.

      Result
      Proceed to OK NG

   
   

   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. Perform the Active Test according to the display on the GTS.

      
      Body Electrical > Main Body > Active Test

      Tester Display	Measurement Item	Control Range	Diagnostic Note
      Front Fog Light Relay	Front fog lights	OFF or ON	Light control switch in tail position

      
      Body Electrical > Main Body > Active Test

      Tester Display
      Front Fog Light Relay

      OK
      Front fog light relay operates. (Front fog lights come on.)

      Result
      Proceed to OK NG

   
   

   OK

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

   NG

3. CHECK HARNESS AND CONNECTOR (AUXILIARY BATTERY - FOG FR RELAY)

   
   

   1. Remove the FOG FR relay.

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

      Standard Voltage
      Tester Connection Condition Specified Condition 5 (FOG FR relay) - Body ground Power switch off 11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (FOG FR RELAY INPUT VOLTAGE)

   
   

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

      Standard Voltage
      Tester Connection Condition Specified Condition 2 (FOG FR relay) - Body ground Light control switch in tail or head position 11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   CHECK HARNESS AND CONNECTOR (FOG FR RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) Click here

   OK

5. INSPECT FOG FR RELAY

   
   

   1. Inspect the FOG FR relay.

      Click here

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE FOG FR RELAY

   OK

6. CHECK HARNESS AND CONNECTOR (FOG FR RELAY - FRONT TURN SIGNAL LIGHT ASSEMBLY)

   
   

   1. Disconnect the A21 front turn signal light assembly LH connector.

   2. Disconnect the A12 front turn signal light assembly RH connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3 (FOG FR relay) - A21-2 (B) Always Below 1 Ω 3 (FOG FR relay) - A12-2 (B) Always Below 1 Ω 3 (FOG FR relay) or A21-2 (B) - Body ground Always 10 kΩ or higher 3 (FOG FR relay) or A12-2 (B) - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

7. CHECK HARNESS AND CONNECTOR (FOG FR RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

   
   

   1. Disconnect the 3A 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 1 (FOG FR relay) - 3A-52 Always Below 1 Ω 1 (FOG FR relay) or 3A-52 - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

8. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

   

   *a

   Component without harness connected (Instrument Panel Junction Block Assembly)

   -

   -

   
   

   1. Remove the instrument panel junction block assembly.

      Click here

   2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3A-52 - MB-7 (FFGO) Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   OK

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

   NG

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

9. CHECK HARNESS AND CONNECTOR (FOG FR RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

   
   

   1. Disconnect the 3D 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 2 (FOG FR relay) - 3D-11 Always Below 1 Ω 2 (FOG FR relay) or 3D-11 - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR