a/c fan control speed intermittently not working
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Instructor
Joined: Feb 2010
Posts: 172
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From: Louisiana
a/c fan control speed intermittently not working
I have a 99 with dual zone and recently I have been having problems getting the blower fan to start blowing. Usually I have to push the up and down about 200 times and then it will finally start blowing but it picks whatever speed it chooses (all speeds do work). Eventually it will allow adjustment up and down but not always a guarantee, and I have started noticing that the temp displayed is not always correct either. I also have no codes so Im not sure where to start.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Well,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, If it were ME,,,,, I would have to say you have a head module issue. Instead of $hit-canning your head unit, I would remove it, open it up and examine the circuit board for COLD SOLDER JOINTS!
GM Delphi SUCKS for circuit board solder reliability. The surface mount components pop off the board like pop corn. Use a magnifying glass and look at ALL the connections on the board and repair by re-soldering.
Bill
GM Delphi SUCKS for circuit board solder reliability. The surface mount components pop off the board like pop corn. Use a magnifying glass and look at ALL the connections on the board and repair by re-soldering.
Bill
Last edited by Bill Curlee; Aug 18, 2013 at 10:09 PM.
1st Gear
Joined: Jan 2013
Posts: 1
Likes: 0
From: Stuart Florida
A/C module
I have the exact same problem on my 98. Gotta push the fan speed a bunch of times and sometimes it works and sometimes it doesn't. I have the control module out now, found some bad solder joints but I think they are for the display.
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From: Cape Coral, Florida
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Joined: Oct 2004
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Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
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From: Southlake, TX
I did this repair a couple of years ago. I was rather intimidated to begin this project. As Bill stated, grab a magnifying glass and solder. Easy peasy.
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