LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mazda >> 2003 >> Protege5 Standard >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass/Windows/Mirrors >> Filament Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Filament Inspection

  1. Turn the ignition switch to ON position.
  2. Turn the rear window defroster switch to ON.
  3. Connect the positive (+) lead of the voltmeter to the positive side of each filament and the negative (-) lead to ground.
    CAUTION:
    • Directly touching the rear window defroster filament with the lead of the circuit tester will damage it. Wrap aluminum foil around the end of the lead and test the filament by touching it with the foil.
  4. Gradually, slide the positive (+) lead from the positive side to the negative side and measure the voltage. Verify that the voltage decreases accordingly.
    • If the voltage is not as specified or it changes rapidly, the filament is faulty. Repair the filament.
    Fig 1: Wrapping Aluminum Foil Around End Of The Lead
    G01915092Courtesy of MAZDA MOTORS CORP.
    Fig 2: Voltage Specification Table
    G01915093Courtesy of MAZDA MOTORS CORP.
    Fig 3: Inspecting Filament
    G01915094Courtesy of MAZDA MOTORS CORP.