AC Blower question
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AC Blower question
I have a low mileage 07 C6 and recently I started having a strange problem with the blower motor. When you start the car, the AC works fine and the fan blows just fine, but after about 20-30 minutes of driving, the velocity of the fan gets less and less until it is not really blowing. I still feel cold air coming out of the vents, but the fan has no force, although I still hear it running. If I turn the car off then back on, the cycle starts all over again. Never had anything like this happen, just wondering if anyone else has. I don't know what to replace to fix it, blower motor or something else.
Any opinions would be appreciated.
Any opinions would be appreciated.
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Sounds to me like you have it set to "auto" mode and it's working as it should. You set the temp you want and the system cools to that temp and gradually slows the fan down as it does so.
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I have a low mileage 07 C6 and recently I started having a strange problem with the blower motor. When you start the car, the AC works fine and the fan blows just fine, but after about 20-30 minutes of driving, the velocity of the fan gets less and less until it is not really blowing. I still feel cold air coming out of the vents, but the fan has no force, although I still hear it running. If I turn the car off then back on, the cycle starts all over again. Never had anything like this happen, just wondering if anyone else has. I don't know what to replace to fix it, blower motor or something else.
Any opinions would be appreciated.
Any opinions would be appreciated.
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From: Below the bottom of Berby Hollow, NYS
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So I take it that you tried to increase the fan speed manually and it was no use?
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Melting Slicks
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+1, Have mine set to Auto all the time and it does the same. If the temp inside starts to get hotter again, the fan should adjust appropriately to keep the car at a very even (set) temp 
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Yes, exactly. No matter what I did, the fan speed wouldn't increase, trying every mode possible. As I said though, oddly enough, if the car was turned off and restarted the fan started blowing out just fine for about 20 minutes then fades to nothing.
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I would have thought that the fan was overheating after a while but you are saying that if you turn off the car and immediately restart then the fan is back to full force? Also, you are saying that you hear the fan running but don't feel the air coming out of the vents? Could it be coming out of the vents at your feet? Do you feel anything there or the front defroster?
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I would have thought that the fan was overheating after a while but you are saying that if you turn off the car and immediately restart then the fan is back to full force? Also, you are saying that you hear the fan running but don't feel the air coming out of the vents? Could it be coming out of the vents at your feet? Do you feel anything there or the front defroster?
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I would have thought that the fan was overheating after a while but you are saying that if you turn off the car and immediately restart then the fan is back to full force? Also, you are saying that you hear the fan running but don't feel the air coming out of the vents? Could it be coming out of the vents at your feet? Do you feel anything there or the front defroster?
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From: Austin TX
This sounds like classic blower motor resister failure. Same voltage is going to the blower, but the resister adjusts what voltage the blower sees which is how the speed is controlled. The lower the speed the more heat is given off on heatsinks. So you turn on car and it's able to go full speed; as you drive this failing resister starts getting more and more resistance on line to blower until finally the blower is barely getting any power at all.