On-Vehicle Inspection

CHECK REAR WINDOW DEFOGGER SYSTEM OPERATION
1. When the engine switch is turned on (IG) and the defogger switch is pressed, check that the rear window defogger operates.
  HINT:
  
  After 15 minutes, check that the defogger automatically turns OFF.

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 that have abrasive ingredients.

Fig 1: Inspecting Back Window (Defogger Wire)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
When measuring voltage, wrap a piece of tin foil around the tip of the negative rester probe and press the foil against the wire with your finger, as shown in Fig 2 .

Fig 2: Measuring Back Window (Defogger Wire) Voltage

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Turn the engine switch on (IG).
Turn the defogger switch ON.

Check the voltage at the center of each defogger wire, as shown in Fig 3 .

Standard voltage

STANDARD VOLTAGE CRITERIA

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

Fig 3: Checking Defogger Wires For Breaks

HINT:

If there is approximately 10 V, the wire may be faulty between the center of the wire and the wire and 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.

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 drops from approximately 10 V to 0 V is the place where the defogger wire is broken.
HINT:

If the defogger wire is not broken, the voltmeter should indicate 0 V at the positive (+) end of the defogger wire but gradually increases to approximately 12 V as the meter probe moves to the other end.