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2005 GMC Envoy Question: loud noise from fan, comes and goes, change fan 2 times what controls voltage to fan

 

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fanboy, Charlotte, NC, September 10, 2010, 13:52
 Rookie

i've been fighting this problem for 10 weeks. the cooling fan will sound like a large blower at times. the fan been replaced two times and will be replaced again on monday. what controls the voltage going to the fan motor. what sensors control it. this problem comes and goes, it will run good for 2 to 4 days then start acting up. the computer code show it to be fan speed to high. the dealership is working on it. they are the ones who changed out the cooling fan the first time. what else controls the fan.

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  • Answer #1

    Oakman September 10, 2010, 14:02
     Master

    The speed of the cooling fan on your 2005 GMC Envoy is controlled by the PowerTrain Control Module (PCM). That being said, it is not uncommon to find a broken wire in the harness from the fan clutch to the connector on the side of the fan shroud. If you are replacing just the fan clutch and not the harness a broken wire could be your problem. I have found that most aftermarket fan clutches for these vehicles don't come with the harness. The fan clutch available from A/C Delco may cost a little more but it comes with the short wire harness.

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    fanboy, September 18, 2010, 11:58
     Rookie

    thanks for the help. the car dealership did change out the fan with wire harness both times. the fan was changed out on tuesday of this week. so far so good, no loud noise. they said it had grounded out inside of the clutch housing. but i did repair a bad front low beam headlight before they changed the fan because the connector was almost burned into. loose connection maybe or over voltage, or something else. it had over heated for some reason. but right now everything is ok. another shop "Mr. Transmission" said the noise was ciming from the transmission. i believed they and the worked on the transmission but the noise was not going away. they charged me 2500. tring to get my money back. thanks again for your help.

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  • Answer #2

    Visitor, December 24, 2010, 11:08

    where are you buying your fan also if you still have a code it needs reset in order for the fan to work properly and if your buying your fan through gm that may be your problem the censor is on the front of the fan thats whats bad but you have to replace the entire unit go to advanced auto or auto zone and but a life time warrenty one not one of those reject gm fans

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