Heater controls and What is this plug for?

[trucker79005]

Well, I pulled out the radio and heater controls to figure out why my heater blew hot air when on cold. I found the cable unhooked that went to the door and it looks like the plastic valve on the heater controls that the vacuum hoses hook has a nipple broke off. I've checked American parts depot and Kennedy American and didn't see the part but I'm not sure what its proper name would be. Anybody know if a replacement is possible??

Also found these wires that weren't hooked to anything and was just curious if anyone knew what they were for. I'm not really sure what diagram you would look at since its not hooked to anything. I think everything is hooked up to my radio. There is the Red and Blue wires that go into this T type connector and then the orange wire that has what I might call a bullet type connector.

Also, does anyone know what screws to use for the dash. I seem to be missing a few.

[AMC of Houston]

The vacuum control is a 3693112 "Switch, Vacuum" (or J3693112 in MOPAR language).    They are not available new; but the same switch was used on all 1978 thru 1988 AMC passenger cars, except Pacer.   Hopefully you can find a good used one.

I'll pipe up later if I find out anything on my wiring diagrams about your wires (look "radio-ish" to me).

[mo.eagles]

All orange wires go to lights . Dash lights ,glove box light , courtesy lights, radio light, etc... If it is tan with a stripe it goes to a power amp . The red and blue is the ETR connection . The vacuum switch controls the water valve under the hood . It may be stuck in the heat position so you will get hot air all the time.

[trucker79005]

The vacuum control is a 3693112 "Switch, Vacuum" (or J3693112 in MOPAR language).    They are not available new; but the same switch was used on all 1978 thru 1988 AMC passenger cars, except Pacer.   Hopefully you can find a good used one.

Thanks so much for that. I had a feeling i wouldn't find them new. Thinking i can just run vacuum straight to the control under the hood for summer until i can find one. I hope.

All orange wires go to lights . Dash lights ,glove box light , courtesy lights, radio light, etc... If it is tan with a stripe it goes to a power amp . The red and blue is the ETR connection . The vacuum switch controls the water valve under the hood . It may be stuck in the heat position so you will get hot air all the time.

Awesome information! Saving this for future reference. Unfortunately you lost me on "ETR". Maybe if I thought about it long enough it would come to me... or not. I am wondering if the valve under the hood is stuck also but i know for sure that the vacuum lines were not hooked up to the back of the Switch and it is broke.

[amarshall]

If the heater bypass valve under the hood is frozen, a cheaper replacement can be used from a Jeep Cherokee.  They look different and are plastic, but they are only about $15 and have the same function.  The plastic version is 5/8" on all connections and the original Eagle one is 3/4" on a couple legs so original hoses may be loose.  I wrapped mine with some rubber stretchy tape and the 3/4" hose sealed fine.

My original:


and the Cherokee version:

[mo.eagles]

ETR is energy transfer relay . For the Flux capacitor.    I have no idea what it is . I found it in the diagrams when I had wiring issues awhile back and I've been trying to figure it out.

[AMC of Houston]

ETR is the "fancy" radio - Electronically Tuned Radio.

[mo.eagles]

ETR is the "fancy" radio - Electronically Tuned Radio.

I thought that's what it was but I did not want to guess .

[trucker79005]

ETR is energy transfer relay . For the Flux capacitor.    I have no idea what it is . I found it in the diagrams when I had wiring issues awhile back and I've been trying to figure it out.

funny

ETR is the "fancy" radio - Electronically Tuned Radio.

thanks:) Guess I don't really need that

[vangremlin]

...... a cheaper replacement can be used from a Jeep Cherokee.  They look different and are plastic, but they are only about $15 and have the same function. 

Which year Cherokee does that come off of?  Thanks.

[AMC of Houston]

Or you can get the "1980-only" version cheap on RockAuto right now (~$20).    Has trhe same form/fit/function; but you have to add a pipe plug to the sensor hole.

[amarshall]

The heater control valve I used was from Rock Auto also, it is a "Four Seasons 74777".  I found it by looking under a 1994 Jeep Cherokee, but it might also be found in other years.

[AMC of Houston]

Good to know on the Jeep part.   I just checked RockAuto again for the 1980 versions; and they're all gone!!    I got 2 of them -- the Four Seasons number was 74704 if anyone finds them elsewhere.   I hope Den members got the others!

[mudkicker715]

I just saw that i have a nos one while packing up last night. No i am not giving it up. Just glad i have a replacement.

[sandmtnjeep]

American Part Depot had them a short while back for $25.  They required a plug.