Front Fog Light Circuit [12/2012 - 10/2015]: Procedure

1. Using the Techstream, perform the Active Test.

   Refer to DATA LIST / ACTIVE TEST [12/2012 - ] .

   OK

   Headlight relay operates (low beam headlights come on).

   Body Electrical > Main Body > Active Test 

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

   Body Electrical > Main Body > Active Test 

   Tester Display
   Front Fog Light Relay

Result: 

OK 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [12/2012 - ]  . 

Result: 

NG 

See step  2

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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: 

NG 

REPLACE FRONT FOG LIGHT RELAY (FOG FR) 

Result: 

OK 

See step  3

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a	Front view of wire harness connector (to Front Fog Light Relay)

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

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   Front fog light relay terminal 3 - Body ground	Always	11 to 14 V

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  4

1. Remove the front fog light from the No. 2 engine room relay block and junction block assembly.
2. Disconnect the 3B 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
   Front fog light relay terminal 1 - 3B-28	Always	Below 1 Ω
   3B-28 - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  5

1. Remove the front fog light from the No. 2 engine room relay block and junction block assembly.
2. Disconnect the 3B 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
   Front fog light relay terminal 2 - 3B-56	Always	Below 1 Ω
   3B-56 - Body ground	Always	10 kΩ or higher

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  6

1. Remove the instrument panel junction block assembly.

   Refer to REMOVAL [12/2012 - ] .

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Refer to REMOVAL [12/2012 - ] .

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

   Standard Resistance

   Tester Connection	Switch Condition	Specified Condition
   A-13 (FFGO) - 3B-56	Always	Below 1 Ω

Result: 

OK 

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [12/2012 - 10/2015]  . 

Result: 

NG 

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to  REMOVAL [12/2012 - ]  .