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Climate Control Fan on?


Old 01-05-2012, 03:06 AM
vroomazoom's Avatar
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Join Date: Nov 2011
Location: Pearl City, Hawaii
Posts: 61
Default Climate Control Fan on?

After coming home from work, I decided to familiarize myself with the undercarriage and wipe down the undercarriage and just noticed my fan blower came on for a few seconds and turned off and that happened several times before it completely shut off. This is all with the key out of the ignition. I tried looking through my manual for such operation, and also the search feature on the forum but all I got was the thread about fan blower "not" working and how to fix it.

Just wondering if this is normal? Is it the climate control fan coming on or is it something else? All I see is that its another thing draining the battery.
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Old 01-05-2012, 06:32 AM
Join Date: Aug 2009
Posts: 2,652
Default interesting

ive seen the fan sw schematic so many times,,,but i looked again,and sure enuf, i found nothing!!
it looks like a mechanical sw only with no "computer intervention"
it appears that the only ground for the motor is thru the manual sw on the dash. IF something else turned it on it would be at the speed the sw was left at and we would likely notice it at high speed,??
the sw ground does goto a "logic'block only when in the off position,for some reason.
i never bother turning mine off because the ign kills the hvac relay,killing everything. ??
so i see no way that it the blower motor. ?no good reason why it would be ,huh?
so if it iz,i dont see how!

edit, still looking.
the ground that the sw puts on the logic module is there only in the off position? in the off pos there is NOTHING touching any speed contact. no way for the fan to run,or be turned on by comp. ??

Last edited by drtom; 01-05-2012 at 07:03 AM.
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Old 01-26-2012, 12:39 AM
vroomazoom's Avatar
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Join Date: Nov 2011
Location: Pearl City, Hawaii
Posts: 61

I'm still stumped on why it comes on with key in hand. Looking over the wiring schematics too and found the same as you drtom.
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