Air blows from every vent

[greenz97]

No matter where i place the control knob for where the air goes it comes it out of every vent low and high mainly the middle vents though any ideas

might as well combine two questions here

the fan setting works on low, med-low, and high. but not med-high could it be the resistor because i thought when that went out it made all the settings besides high not work. any thoughts on this as well would be helpful

 

[HotWheelsBurban]

Part of it probably is, the gaskets/seals on the evaporator case have shrunk a little bit, so air is getting places it shouldn't be (based on the switch position). My '97 does this, where the air conditioning comes out some through the defrost ducts in the front of the dashboard. This fogs the bottom of the windshield up, not good anytime! So what I came up with as a remedy (since the dash in this truck is still nice and I don't want to take it apart!) is get a hand towel and fold it across the dashboard, over the defrost ducts. Fixed the issue and only cost a couple of bucks.....

 

[east302]

the fan setting works on low, med-low, and high. but not med-high could it be the resistor because i thought when that went out it made all the settings besides high not work. any thoughts on this as well would be helpful

Disconnect the resistor and check for voltage at each wire coming from the blower switch. You should get 12V (battery voltage) on each, the light blue being medium-high.

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If you have voltage, then I’d suspect the resistor. If you do not have voltage, then it’s likely the blower switch which can be removed from the panel. But, check that its wiring connector isn’t melted - if it is, replace it. GM part number 12064998.

 

[Onizukachan]

Mine was the switch, same issue. For $11 I got one off eBay and replaced it First.

 

[Cadillac Bob]

And check your connections have you gotten into the dash lately? I have and same thing happened but after I got back into dash realized that connection on the drivers side was not connected so after that everything worked as it should. But if not then yes definitely narrow it down to one of 2 parts. I have a squeak noise from blower but I have a
“truck driver flashlight” stowed on floor between center console and passenger seat that’s a 18” metal baseball bat with a flashlight at the top I tap the blower once in a while and no more squeaking. Lol

 

[bbenton50]

I'm having the same problem with air blowing out of all vents? Any ideas what it could be?