a/c heater control

[hawkeye]

i'm sure i ran across a detailed posting of how to repair your heater a/c control switch.  can't seem to find it now. can anyone point me in the right direction? thanks,  hawkeye

[six-tee-nine]

I never made a posting about it but a did mine a while ago. Will dig trough my pictures when I get home tonight and get back to you.

[six-tee-nine]

Ok, here we go sorry for the delay......

The AC pushbutton control is a sealed unit but however it is rebuildable. If you carefully grind away or cut away the 6 "buttons" wich are melted on to close the control you can open up the control unit.



Be very carefull with the sliding plates you find in the actuator. Take them out as a package and dont mess around with these. You can clean these but they are kinda brittle when unsupported in the housing. Whatever you do make 200% sure you know in witch order they were and how they were in the housing. If you loose the right order they were in then later on your pushbutton function wont work like it should.



Then you can clean the actual push buttons. clean the brass spurs gently with for instance a small Dremel steel wire brush. Make sure they arent bent too far inwards. You want them to make contact with the plates in the housing when you put them back in.



The back plate of the housing is where the vacuum for the AC unit is divided to all the actuators on the heater core. In the below picture you can see the rubber that slides from left to right depending on the puttons pushed by the guy behind the steering wheel.
Make sure the tiny holes are clean and lightly greas the rubber so it slides light.



Then you need to drill small holes in the housing where the 6 plastic rivets were you just ruined to open the housing. Then you can put the whole thing toghether and put the back plate on agian. then you take 6 small screws not oo large you dont want the 40 year old plastic to crack. and you're done....



The fan switch is an easy one, just bend the 4 legs on back of the switch and open it up. Make sure the brass contact are clean and everything moves smoothly and put it back together.

[hawkeye]

thanks!!!!!  that's exactly what i needed.  the only problem is that my switch was already apart and i have no idea what order or how many sliding plates there are.  i think i have 4 and all seem to be in good shape.   anyone have a picture of how they should go?  thanks again.

[six-tee-nine]

IIRC Then 4 is the correct number. In the second picture you can see them laying on my table in the top of the picture. I remember that when you put them toghether they align and they form the same shape. However I cant remember how they need to go in because left or right is different.

Maybe If you look at the control buttons you can see what happens if you push the buttons. AC OFF means all buttons come back to "neutral" the other buttons stay depressed when you push them meaning if you push "defrost" for instance then the MAX AC button returns if it was pressed before.
If you put it together with the screws you can test it and when wrong you can alway open it up again to turn the plates 180° I guess there is a 50% chance on having it right.....

Good luck