Window Defogger System: Inspection

INSPECT OUTER REAR VIEW MIRROR ASSEMBLY LH (w/ Mirror Heater)

Apply battery voltage and check operation of the mirror heater.

MEASUREMENT CONDITION SPECIFIED CONDITION CHART

Measurement Condition	Specified Condition
Battery positive (+) → Terminal 1 (HEATER+) Battery negative (-) → Terminal 5 (HEATER-)	Mirror becomes warm

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

Fig 1: Inspecting Outer Rear View Mirror Assembly LH (W/ Mirror Heater)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT OUTER REAR VIEW MIRROR ASSEMBLY RH (w/ Mirror Heater)

Apply battery voltage and check operation of the mirror heater.

MEASUREMENT CONDITION SPECIFIED CONDITION CHART

Measurement Condition	Specified Condition
Battery positive (+) → Terminal 1 (HEATER+) Battery negative (-) → Terminal 5 (HEATER-)	Mirror becomes warm

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

Fig 2: Inspecting Outer Rear View Mirror Assembly RH (W/ Mirror Heater)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT BACK WINDOW (DEFOGGER WIRE)

Inspect the back window (defogger wire).
NOTE:
- When cleaning the glass, wipe the glass along the wire using a soft, dry cloth. Take care not to damage the wires.
- Do not use detergents or glass cleaners that have abrasive ingredients.
- When measuring voltage, wrap a piece of tin foil around the tip of the negative tester probe and press the foil against the wire with your finger, as shown in the illustration.
  
  Fig 3: Inspecting Back Window (Defogger Wire)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Turn the ignition switch ON.
Turn the defogger switch ON.

Fig 4: Inspecting Back Window (Defogger Wire)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the voltage at the center of each defogger wire as shown in the illustration.

Standard voltage

TERMINALS VOLTAGE CHART

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

HINT:

If there is approximately 10 V, the wire may be faulty between the center of the wire and the wire end on the battery side. If there is no voltage, the wire may be faulty between the center of the wire and the wire end on the ground side.

Fig 5: Measuring Voltage At Center Of Defogger Wire

Place the voltmeter's positive (+) lead against the defogger wire on the battery side.
Place the voltmeter's 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 voltage jumps from approximately 10 V to 0 V is where the defogger wire is broken.
HINT:

If the defogger wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the defogger wire and gradually increases to approximately 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 both sides of the wire.
3. Thoroughly mix the repair agent (DuPont paste No. 4817 or equivalent).
  
  Fig 6: Placing Masking Tape
  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 again for at least 24 hours.
  
  Fig 7: Applying Small Amount Of Agent To Wire Using Fine Tip Brush
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

INSPECT DEFOGGER RELAY

Marking: DEF

Remove the DEF relay from the engine room R/B.

Measure the resistance of the relay.

Standard resistance

TESTER CONDITION SPECIFIED CONDITION CHART

Tester Condition	Specified Condition
3 - 4	Below 1 Ω
3 - 5	10 kΩ or higher
3 - 5	Below 1 Ω (when battery voltage is applied to terminals 1 and 2)

If the result is not as specified, replace the relay.

Fig 8: Inspecting Heater Blower Motor Relay