defrost and heater not blowing

1992 LEXUS SC 300
140,000 MILES
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JPCADA55
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  • 2 POSTS
I have a Lexus sc300 and the heater/def. stopped working. A charger came apart in the cig. lighter and possibly shorted something. I have changed three fuses inside by the driver door panel, also the main relay in the engine bay and still dead, ideas? not many replaced everything I found referring to heat/def/ac, still no life?
Dec 16, 2011 at 7:33 AM
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RIVERMIKERAT
  • ✓ASE Certified Mechanic
  • 6,110 POSTS
  • ASE Certified Mechanic
Does the blower motor come on? Can you hear the blend doors in the airbox opening and closing when you adjust the temperature or move the selector to change from vent to heat to defrost?
Dec 16, 2011 at 7:38 AM
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JPCADA55
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  • 2 POSTS
No Cannot hear any parts or blower movement, seems like that whole package is dead including mirror and rear window defrost, all dead?
Dec 16, 2011 at 8:00 AM
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RIVERMIKERAT
  • ✓ASE Certified Mechanic
  • 6,110 POSTS
  • ASE Certified Mechanic
I apologize about the delay in getting back to you, the system failed to notify me of your response.

Check the defogger relay in the main relay block under the hood for power in and out and switching power. It'll be labeled.

Make sure the blower motor ground wire is plugged in and not broken. Make sure the fuses are all good. Check the blower motor resistor.
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Dec 29, 2011 at 7:54 PM
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