LIGHTING SYSTEM Rear Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives headlight dimmer switch information signals and illuminates the rear fog lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. PERFORM ACTIVE TEST USING GTS (REAR FOG LIGHT RELAY)

   
   

   1. Using the GTS, perform the Active Test.

      Click here

      
      Body Electrical > Main Body > Active Test

      Tester Display	Measurement Item	Control Range	Diagnostic Note
      Rear Fog Light Relay	Rear fog light relay	ON or OFF	The headlight dimmer switch is in the tail position.

      
      Body Electrical > Main Body > Active Test

      Tester Display
      Rear Fog Light Relay

      OK
      Rear fog light relay operates (rear fog lights come on).

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) for LHD: REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) for RHD: REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   NG

2. INSPECT REAR FOG LIGHT RELAY (FOG RR)

   
   

   1. 

      Remove the rear fog light relay from the No. 2 engine room relay block and junction block assembly.

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

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

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE REAR FOG LIGHT RELAY (FOG RR)

   OK

3. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - BATTERY)

   
   
   1. 

      *a	Front view of wire harness connector (to Instrument Panel Junction Block Assembly)

      Remove the instrument panel junction block assembly connector.

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

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

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (REAR FOG LIGHT RELAY [FOG RR] - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

   
   

   1. Remove the rear fog light relay from the No. 4 relay block.

   2. Disconnect the 3C and 3D 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 Rear fog light relay terminal 5 - 3C-25 Always Below 1 Ω Rear fog light relay terminal 2 - 3D-52 Always Below 1 Ω Rear fog light relay terminal 1 - 3C-38 Always Below 1 Ω 3C-25 - Body ground Always 10 kΩ or higher 3D-52 - Body ground Always 10 kΩ or higher 3C-38 - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

   
   

   1. 

      Remove the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

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

      for LHD:

      Click here

      for RHD:

      Click here

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition 3A-1 - 3C-25 Always Below 1 Ω A-27 (RFGO) - 3D-52 Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   OK

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

   NG

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY for LHD: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY for RHD: REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here