Windshield Deicer 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   10 

OK: Go to next step 

1. Select the Active Test using the Techstream to generate a control command, and then check that the windshield deicer 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
   Wiper Deicer	Deicer relay operation	OFF or ON	-

   OK

   Windshield deicer operates normally.

NG → See step   4 

OK: Go to next step 

1. Temporarily replace the display and navigation module display with a new or normally functioning one.
   • w/ Navigation System (for HDD). Refer to REMOVAL
   • w/ Navigation System (for DVD). Refer to REMOVAL
2. Check that the malfunction disappears.

   OK

   Malfunction disappears.

   RESULT
   
   

   Result	Proceed to
   OK (w/ Navigation System [for HDD])	A
   OK (w/ Navigation System [for DVD])	B
   NG	C

C → See step   11 

B → END (DISPLAY AND NAVIGATION MODULE DISPLAY IS DEFECTIVE) 

A → END (DISPLAY AND NAVIGATION MODULE DISPLAY IS DEFECTIVE) 

1. Remove the DEICER fuse from the engine room No. 2 relay block.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   DEICER fuse	Always	Below 1 Ω

NG → REPLACE FUSE 

OK: Go to next step 

Fig 1: Inspecting Towing Converter Relay (Sub Bolt)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the deicer 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 - 5	When battery voltage is not applied between terminals 1 and 2	10 kΩ or higher
   	When battery voltage is applied to terminals 1 and 2	Below 1 Ω

NG → REPLACE DEICER RELAY 

OK: Go to next step 

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the DEICER 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
   Deicer relay terminal 2 - Body ground	Power switch ON (IG)	11 to 14 V
   Deicer 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
   Deicer relay terminal 1 - A51-13 (FDEF)	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

Fig 3: Checking Harness And Connector (Deicer Relay - Windshield Deicer Wire)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Remove the DEICER relay from the No. 3 relay block.
2. Disconnect the A30 windshield deicer wire connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   A30-1 (B2) - Deicer relay terminal 3	Always	Below 1 Ω
   A30-2 (B) - Deicer relay terminal 3
   Deicer relay terminal 3 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

Fig 4: Identifying Windshield Deicer Connector A30

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the A30 windshield deicer wire connector.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   A30-3 (E) - Body ground	Always	Below 1 Ω

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   11 

OK → END (FRONT CONTROLLER IS DEFECTIVE)