Blend door - what and where is it
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09-16-2004, 07:28 PM
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Blend door - what and where is it
#2
09-18-2004, 04:54 PM
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Location: Smithville TX.
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The blend air door is located in the hear/AC plenum. The function of the door is to blend heated air that goes through the heater core with cold air that goes through A/C evaporator. The blend of the hot and cold air makes the desirable temp. air that you ask for via the temp. control. You will find the blend air door located in the black box the houses the heater core and A/C evaporator. Also located in or near the plenum is the A/C heat door, it diverts air either to the heater ducts, or to the A/C registers in the dash. Defroster door that diverts air to the defroster. Look under your dash and find the plenum assembly, some of these door control vacuum actuators may be externally mounted, if so you can remove the vacuum lines and by adding a short piece of vacuum line you can test the vacuum diaphragm in the actuator by sucking on the vacuum line and seeing if the vacuum motor will move. I once had a vacuum motor that had a busted vacuum diaphragm, I replaced it and the problem was fixed. If your truck has an ATC system the problem could be in your ATC sensor. I have seen them go bad too. That is about all I can tell you without a manual in front of me. Hope it helps a little.
Michelle
Michelle
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