Rear Window Defogger System does not Operate: Procedure

1. Ensure the key is inside the cabin.
2. With the brake pedal released, check that the power source mode changes as shown below each time the power switch is pushed.

   OK

   OFF → ON (ACC) → ON (IG) → OFF

NG → See step   11 

OK: Go to next step 

1. Select the Active Test using the Techstream to generate a control command, and then check that the rear window defogger operates.
   NOTE:

   When the Body No. 5 (front controller) related vehicle switch is ON, Active Test items related to the vehicle switch are prohibited (double operation prohibition). Check that the vehicle switches are OFF before performing Active Test.

   BODY NO. 5:
   
   

   Tester Display	Test Part	Control Range	Diagnostic Note
   Rear Defogger operation	Rear window defogger relay operation	OFF or ON	-

   OK

   Rear window defogger operates normally.

   RESULT
   
   

   Result	Proceed to
   OK (for Display and Navigation Assembly)	A
   OK (for Multi-display)	B
   NG	C

C → See step   5 

B → See step   4 

A: Go to next step 

1. Temporarily replace the display and navigation assembly with a new or normally functioning one. Refer to REMOVAL .
2. Check that the malfunction disappears.

   OK

   Malfunction disappears.

NG → See step   12 

OK → END (DISPLAY AND NAVIGATION ASSEMBLY IS DEFECTIVE) 

1. Temporarily replace the multi-display with a new or normally functioning one, w/ navigation system (for DVD). Refer to REMOVAL or w/o navigation system. Refer to REMOVAL .
2. Check that the malfunction disappears.

   OK

   Malfunction disappears.

NG → See step   12 

OK → END (MULTI-DISPLAY IS DEFECTIVE) 

1. Remove the DEFOG H-fuse from the engine room No. 1 relay block.
2. Remove the D-IG1-3 fuse from the driver side junction block.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   DEFOG H-fuse	Always	Below 1 Ω
   D-IG1-3 fuse

NG → REPLACE FUSE 

OK: Go to next step 

Fig 1: Defogger Relay Circuit

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the defogger relay from the No. 3 relay block.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   3 - 4	When battery voltage is not applied between terminals 1 and 2	Below 1 Ω
   3 - 5	When battery voltage is not applied between terminals 1 and 2	10 kΩ or higher
   3 - 4	When battery voltage is applied to terminals 1 and 2	10 kΩ or higher
   3 - 5	When battery voltage is applied to terminals 1 and 2	Below 1 Ω

NG → REPLACE DEFOGGER RELAY 

OK: Go to next step 

Fig 2: Checking Harness And Connector (Defogger Relay - Front Light ECU And Battery)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the DEFOG relay from the No. 3 relay block.
2. Disconnect the A51 front controller connector.
3. Measure the voltage according to the value(s) in the table below.

   Standard voltage

   Tester Connection	Condition	Specified Condition
   Defogger relay terminal 2 - Body ground	Power switch ON (IG)	11 to 14 V
   Defogger relay terminal 5 - Body ground	Always	11 to 14 V

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   Defogger relay terminal 1 - A51-12 (RDEF)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

Fig 3: Checking Harness And Connector (Rear Window Defogger - Defogger Relay And Body Ground)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the S19 and W1 defogger connectors.
2. Remove the DEFOG relay from the No. 3 relay block.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   S19-1 - Defogger relay terminal 3	Always	Below 1 Ω
   W1-1 - Body ground
   Defogger relay terminal 4 - Body ground
   S19-1 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Temporarily replace the front controller with a new or normally functioning one.
2. Check that the malfunction disappears.

   OK

   Malfunction disappears.

NG → See step   10 

OK → END (FRONT CONTROLLER IS DEFECTIVE) 

1. Temporarily replace the air conditioning amplifier with a new or normally functioning one. Refer to REMOVAL .
2. Check that the malfunction disappears.

   OK

   Malfunction disappears.

NG → See step   13 

OK → END (AIR CONDITIONING AMPLIFIER IS DEFECTIVE)