Front Fog Light Circuit [12/2014 - ]: Procedure

1. Check the operation of the taillights and headlights.

   OK

   Taillights and headlights operate normally.

NG → See step   7 

OK: Go to next step 

1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON (IG).
3. Turn the Techstream on.
4. Enter the following menus: Body Electrical / Main Body / Active Test.
5. Perform the Active Test according to the display on the Techstream.
   MAIN BODY
   
   

   Tester Display	Test Part	Control Range	Diagnostic Note
   Front Fog Light Relay	Front fog light relay	ON/OFF	Light control switch is in head position

   OK

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

NG → See step   3 

OK → See step   5 

1. Disconnect the A12 fog light assembly LH connector.
2. Disconnect the A63 fog light assembly RH connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A12-2 (B) - 3C-7	Always	Below 1 Ω
   A63-2 (B) - 3C-7	Always	Below 1 Ω
   3C-7 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Remove the instrument panel junction block assembly. Refer to REMOVAL [12/2014 - ] .
2. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

3. Connect a positive (+) lead from the auxiliary battery to terminal 3E-1.
4. Connect a negative (-) lead from the auxiliary battery to terminal MB-14 (TRLY) and MB-13 (FFGO).
5. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   3C-7 - Body ground	Always	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

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

NG → See step   6 

OK → See step   8