Heat/AC Distribution Troubleshooting/Vacuum Control

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McCSquare

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For the time being i rigged my own defroster system. Patent pending.

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89Suburban

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Quick interuption, 89s do you have the rest of that manual scanned? I wouldnt mind seeing pg178, have Q about switch for rear air....

Let me dig around, very busy today.

For the time being i rigged my own defroster system. Patent pending.

HAHAAHHAHA I love it!! :grd:
 

8T6K5

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Let me dig around, very busy today.

Whenever, no rush. Would like to know the wire sources for the rear ac on-off-on switch, power in and gorund?
 

8T6K5

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McCSquare

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Bumping for any ideas for the next thing to check.

1.) I have heat, and pretty good blower pressure at the upper vents.
2.) The flapper door at the floor does close when I move the control to defrost.
3.) There is no heat nor pressure at either of the vents on the dashboard (defrosters)
4.) I tried sticking my hands under the steering wheel/up under the dashboard and I'm not feeling any significant leak.
5.) In defrost there is still very strong pressure and heat at the upper vents.

What should I check? Think there is a blockage or something? What about the blender door? (I've seen it referenced elsewhere)
 

89Suburban

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Look under the dash behind the glove box area, you will see the piece of ducting that screws to the heater housing that supplies the flow of air to the a/c vents. Unscrew and remove that piece and check the action of the blend door. There is a plastic piece on that door that is notorious for breaking.
 

travisr1988

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I have a quick question, my heater worked, but stopped working one day and started working again the next, 3 months later when I ran a wire through the firewall under the heater box it stopped working again, I found a wire pulled out of the connector at the box in the engine compartment, I promptly repaired the connector and heard a faint click, now I get heat again but the switch to control blower speed seems to have stopped working, low or high doesn't matter, it just seaps out no matter what setting anything is on. What should I be testing to figure this out?
 

McCSquare

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Look under the dash behind the glove box area, you will see the piece of ducting that screws to the heater housing that supplies the flow of air to the a/c vents. Unscrew and remove that piece and check the action of the blend door. There is a plastic piece on that door that is notorious for breaking.

I finally pulled the glovebox and found that blender door white clip was broken! Moved it by hand and bingo... defroster! I can finally ditch that damn dryer vent hose. Hah

Where do I buy a new one? Is there a clever fix I can rig up from the hardware store?
 
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89Suburban

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McCSquare

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travisr1988

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Figured my issue out, the connector at the blower motor for the purple wire (right where it plugs into the motor in the engine bay had broken off and only appeared to be hooked up, pushed it in further and the motor kicked on. Now, my question is can I repair that or do I need a new motor?
 

jonp

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I'm haveing a similar problem to this......when I put the control to defrost mode the blower turns off no air no nothing
 

87scotty

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Bringing this back from the dead I'm trying to find the 2 little plastic clips that go on the door behind the clovebox
 

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