Window Defogger System: Inspection

INSPECT AIR CONDITIONING CONTROL ASSY (AUTO AIR CONDITIONING)

Inspect operation of the defogger timer.
1. Connect the positive (+) lead from the battery to terminal A3-3 and the negative (-) lead to terminal A4-6.
2. Connect the positive (+) lead from the battery to terminal A4-1 through a 1.4 W test bulb.
3. Push the defogger switch ON, check that the indicator light on the switch and the test bulb light up for 12 to 18 minutes, and then the indicator light and the test bulb go off.
  If the result is not as specified, replace the A/C control assy.
  
  Fig 1: Inspecting Air Conditioning Control Assy
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the connector from the A/C control assy.

Check the voltage or continuity of each terminal of the wire harness side connector.

Fig 2: Identifying Control Assembly Wire Harness Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard:

TERMINAL SPECIFIED CONDITION CHART

Terminal No.	Condition	Specified Condition
A4-6 <=> Body ground	Constant	Continuity
A4-1 <=> Body ground	Ignition switch Lock or ACC	No voltage
A4-1 <=> Body ground	Ignition switch ON	Battery positine voltage
A3-3 <=> Body ground	Ignition switch Lock or ACC	No voltage
A3-3 <=> Body ground	Ignition switch ON	Battery positine voltage

If the result is not as specified, there may be a malfunction on the wire harness side.

INSPECT AIR CONDITIONING CONTROL ASSY (AUTO AIR CONDITIONING, W/ EMV & NAVIGATION SYSTEM)

Inspect operation of the defogger timer.
1. Connect the positive (+) lead from the battery to terminal 9 and the negative (-) lead to terminal 10.
2. Connect the positive (+) lead from the battery to terminal 7 through a 1.4 W test bulb.
3. Push the defogger switch ON, check that the indicator light on the switch and the test bulb light up for 12 to 18 minutes, and then the indicator light and the test bulb go off.
If the result is not as specified, replace the A/C control assy.

Fig 3: Inspecting Air Conditioning Control Assy
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Disconnect the connector from the A/C control assy.

Check the voltage or continuity of each terminal of the wire harness side connector.

Standard:

TERMINAL SPECIFIED CONDITION CHART

Terminal No.	Condition	Specified Condition
10 <=> Body ground	Constant	Continuity
7 <=> Body ground	Ignition switch Lock or ACC	No voltage
7 <=> Body ground	Ignition switch ON	Battery positine voltage
9 <=> Body ground	Ignition switch Lock or ACC	No voltage
9 <=> Body ground	Ignition switch ON	Battery positine voltage

Fig 4: Identifying Wire Harness Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the result is not as specified, there may be a malfunction on the wire harness side.

INSPECT OUTER REAR VIEW MIRROR ASSY LH (w/ OUTER MIRROR HEATER)

Inspect operation of the mirror heater.

Standard:

TERMINAL SPECIFIED CONDITION CHART

Measurement Condition	Specified Condition
Battery positive (+) --> H+ (5) Battery negative (-) --> H- (12)	Mirror becomes warm

Fig 5: Identifying Outer Rear View Mirror Assy LH Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the result is not as specified, replace the mirror assy.

INSPECT OUTER REAR VIEW MIRROR ASSY RH (w/ OUTER MIRROR HEATER)

Inspect operation of the mirror heater.

Standard:

TERMINAL SPECIFIED CONDITION CHART

Measurement Condition	Specified Condition
Battery positive (+) --> H+ (5) Battery negative (-) --> H- (12)	Mirror becomes warm

If the result is not as specified, replace the mirror assy.

Fig 6: Identifying Outer Rear View Mirror Assy RH Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT OUTER MIRROR HEATER SWITCH ASSY (w/ OUTER MIRROR HEATER)

Inspect operation of the defogger switch illumination.

Standard:

TERMINAL SPECIFIED CONDITION CHART

Measurement Condition	Specified Condition
Battery positive (+) --> ILL+ (1) Battery negative (-) --> ILL- (2)	Illumination light lights up

If the result is not as specified, replace the outer mirror heater switch assy or bulb.

Fig 7: Identifying Outer Mirror Heater Switch Assy Connector Terminal

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Inspect operation of the defogger timer.
1. Connect the positive (+) lead from the battery to terminal 4 and the negative (-) lead to terminal 3.
2. Connect the positive (+) lead from the battery to terminal 5 through a 1.4 W test bulb.
3. Push the outer mirror heater switch ON, check that the indicator light on the switch and the test bulb light up for 5 minutes, and then the indicator light and the test bulb go off.
If the result is not as specified, replace the outer mirror heater switch assy.

Fig 8: Inspecting Operation Of Defogger Timer
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT BACK WINDOW (DEFOGGER WIRE)

NOTE:

When cleaning the glass, wipe the glass along the wire using a soft and dry cloth. Take care not to damage the wires.
Do not use detergents or glass cleaners including abrasive ingredients.
When measuring voltage, wrap a piece of tin foil around the tip of the negative probe and press the foil against the wire with your finger, as shown in the Illustration

Fig 9: Inspecting Back Window (Defogger Wire)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Turn the ignition switch ON.
Turn the defogger switch ON.

Inspect the voltage at the center of each heat wire, as shown in the illustration.

Standard:

VOLTAGE SPECIFIED CONDITION CHART

Voltage	Criteria
Approx. 5 V	Okay, wire is not broken
Approx. 10 V or 0 V	Wire is broken

Fig 10: Inspecting Voltage At Center Of Each Heat Wire

HINT:

If there is approximately 10 V, the wire may be broken between the center of the wire and the positive (+) end. If there is no voltage, the wire may be broken between the center of the wire and the ground.

Place the voltmeter positive (+) lead against the defogger wire on the battery side.
Place the voltmeter negative (-) lead with the foil strip against the wire on the ground side.
Slide the positive (+) lead from the battery side to the ground side.
The point where the voltmeter deflects from several V to 0 V is the place where the defogger wire is broken.

Fig 11: Identifying Broken Defogger Wire
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the defogger wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the defogger wire but gradually increases to about 12 V as the meter probe moves to the other end.
If necessary, repair the defogger wire.
1. Clean the broken wire tips with grease, wax and silicone remover.
2. Place the masking tape along the both sides of the wire.
3. Thoroughly mix the repair agent (Dupont paste No. 4817).
  
  Fig 12: Placing Masking Tape Along Both Sides Of Wire
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Using a fine tip brush, apply a small amount of the agent to the wire.
5. After a few minutes, remove the masking tape.
  NOTE: Do not repair the defogger wire for at least 24 hours.
  
  Fig 13: Using Fine Tip Brush To Apply Small Amount Of Agent To Wire
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002