Rear Window Defogger System does not Operate: Procedure

1. Select the DTC check on the Techstream to check for communication errors.

   Result

   Not output DTC codes	A
   Output DTC codes (Multiplex communication)	B
   Output DTC codes (CAN communication)	C

C → GO TO CAN COMMUNICATION SYSTEM 

B → GO TO MULTIPLEX COMMUNICATION SYSTEM 

A: Go to next step 

1. Select the Active Test, use the Techstream to issue a control command, and then check the window defogger operation.

   Air Conditioner

   Tester Display	Test Part	Control Range	Diagnostic Note
   Defogger Rly-R	Turns rear window defogger	OFF/ON	-

   Result

   OK (with Navigation System)	A
   OK (without Navigation System)	B
   NG	C

C → See step   9 

B → See step   5 

A: Go to next step 

1. Replace the multi-media module display.

NEXT: Go to next step 

1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

NG → REPLACE A/C AMPLIFIER ASSEMBLY 

OK → END 

1. Replace the integration control & panel.

NEXT: Go to next step 

1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

OK → END 

NG: Go to next step 

1. Replace the radio receiver assembly.

NEXT: Go to next step 

1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

NG → REPLACE A/C AMPLIFIER ASSEMBLY 

OK → END 

1. Select the Active Test, use the Techstream to issue a control command, and then check the DEFOG relay operation.
2. Check that operation sound of the DEFOG relay is heard.

   Result

   Relay operating sound is heard	OK
   Relay operating sound is not heard	NG

OK → See step   13 

NG: Go to next step 

Refer to ON-VEHICLE INSPECTION

NG → REPLACE DEFOG RELAY 

OK: Go to next step 

1. Disconnect the DEFOG relay.
   Fig 1: Identifying Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Voltage

   Engine room No. 1 R/B, J/B 

   Tester Connection	Condition	Specified Condition
   1 - Body ground	Engine switch on (IG)	10 to 14 V

NG → REPAIR OR REPLACE LH-IG FUSE OR HARNESS AND CONNECTOR 

OK: Go to next step 

1. Disconnect the DEFOG relay and A/C amplifier assembly connector.
   Fig 2: Identifying Wire Harness (Defog Relay - A/C Amplifier Assembly)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Resistance

   Tester Connection	Condition	Specified Condition
   2 - J58-3	Always	Below 1 Ω
   2 - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPLACE A/C AMPLIFIER ASSEMBLY 

Refer to ON-VEHICLE INSPECTION

NG → REPLACE DEFOG RELAY 

OK: Go to next step 

1. Disconnect the DEFOG relay.
   Fig 3: Identifying Relay Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage and resistance according to the value(s) in the table below.

   Resistance

   Engine room No. 1 R/B, J/B 

   Tester Connection	Condition	Specified Condition
   4 - Body ground	Always	Below 1 Ω

   Voltage

   Engine room No. 1 R/B, J/B 

   Tester Connection	Condition	Specified Condition
   5 - Body ground	Engine switch on (IG)	10 to 14 V

NG → REPAIR OR REPLACE DEFOG FUSE OR HARNESS AND CONNECTOR 

OK: Go to next step 

1. Disconnect the noise filter connectors.
   Fig 4: Inspecting Noise Filter

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Resistance

   Tester Connection	Condition	Specified Condition
   A1 - B1	Always	Below 1 Ω
   A1 - Body ground	Always	10 kΩ or higher

NG → REPLACE NOISE FILTER 

OK: Go to next step 

1. Disconnect the DEFOG relay and defogger wire connectors.
   Fig 5: Identifying Wire Harness (Defog Relay - Noise Filter)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance according to the value(s) in the table below.

   Resistance

   Tester Connection	Condition	Specified Condition
   3 - Q21-1	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Measure the resistance according to the value(s) in the table below.
   Fig 6: Identifying Wire Harness (Defogger Wire Connector - Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Resistance

   Tester Connection	Condition	Specified Condition
   P19-1 - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → REPAIR OR REPLACE REAR WINDOW DEFOGGER WIRE