HVAC Controller
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From: 3rd rock
HVAC Controller
I took my HVAC controller apart tonight to try and figure out if the problem I am having with the flaps is related to a bad resistor or something else in the controller. Does anyone know, of a good trouble shooting guide for this controller and can anyone tell me if there should be any grease over the four metalic tracks that the arm slides over or if it should be clean.
Chronic Tool Dropper
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The traces on the board are normally lubricated slightly, just enough to keep the wiper arm pad from tearing the traces from the board.
All that said, most flap problems are from deteriorated rubber elements in the flap actuators. Vacuum runs from the accumulator in the left front wheelhouse, through the cross-connector by the brake booster, then to the HVAC system and the solenoid-operated valves in that little rack forward of the center console. One or two leaking actuators will kill operation of those remaining. Diagnostic tools are the Mity-Vac and a voltmeter or test light. There are more than a few troubleshooting guides in the various tips sites. Worth a cruise through before you damage the board traces, the fiber optic tubes for the illumination, etc.
All that said, most flap problems are from deteriorated rubber elements in the flap actuators. Vacuum runs from the accumulator in the left front wheelhouse, through the cross-connector by the brake booster, then to the HVAC system and the solenoid-operated valves in that little rack forward of the center console. One or two leaking actuators will kill operation of those remaining. Diagnostic tools are the Mity-Vac and a voltmeter or test light. There are more than a few troubleshooting guides in the various tips sites. Worth a cruise through before you damage the board traces, the fiber optic tubes for the illumination, etc.
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From: Southern Alberta, Canada
You'll have to be a little more specific...........which lines and here did you do the check?
As Bob mentions the HVAC unit is fed vaccum from the engine bay where it is then distributed to 5 accuators. Confirm you have good vaccum to the HVAC unit by measuring the input black line. From there confirm the 5 acctuators hold vaccum.
As Bob mentions the HVAC unit is fed vaccum from the engine bay where it is then distributed to 5 accuators. Confirm you have good vaccum to the HVAC unit by measuring the input black line. From there confirm the 5 acctuators hold vaccum.
Burning Brakes
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From: Myrtle Beach, South Carolina
Can you verify all 5 parts of the AC system holds vacuum by just taking the vacuum line loose that leads into the cabin and test there or are there valves within the ac vacuum system that might isolate a leaking actuator from the test?
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Chronic Tool Dropper
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A thin film of Vaseline is as good as anything, unless you live in Florida. Then, try a thin film of marine wheel bearing grease or some synthetic like Mobil-1 that you can get at the parts place and use for other things. Just a thin film... More will cause problems. If you just used your fingers to get the old stuff off, there's probably plenty still left on the board. It does get old and hard over time. I just don't move the slider much so never worry about it.
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From: Southern Alberta, Canada
Originally Posted by aggravation
Can you verify all 5 parts of the AC system holds vacuum by just taking the vacuum line loose that leads into the cabin and test there or are there valves within the ac vacuum system that might isolate a leaking actuator from the test?
