Auto temp 1-2

SGT FURY

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Can someone briefly explain the auto temp 1-2 to me. I know there is a problem with them working?
One is more desirable than the other?
We’re both available on the same model?
What years did start producing auto temp and when did they stop?
 
Short version: 1971-1973 is fixable. 1969-1970 is another matter entirely.

Longer version: you should search for posts on ATC or AutoTemp authored by @saforwardlook — detailed explanations / answers are all there.
 
Can someone briefly explain the auto temp 1-2 to me. I know there is a problem with them working?
One is more desirable than the other?
We’re both available on the same model?
What years did start producing auto temp and when did they stop?
Auto-Temp showed up in 1967, and was replaced a few years later by Auto-Temp II. In addition to what's available here, there's a wealth of info. on the Imperial Club website, here's the "direct" link:


What I have consistently heard/read over the years is that Auto-Temp II is easier to repair / maintain. I think the system you get (ATC I or ATC II) depends on what year the car was built, not sure when exactly that was, but maybe the above, or someone else on here can chime in with that. Hope this helps.
 
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Short version: 1971-1973 is fixable. 1969-1970 is another matter entirely.

Longer version: you should search for posts on ATC or AutoTemp authored by @saforwardlook — detailed explanations / answers are all there.

I would just add that Autotemp 1 vehicles started as early as 1967 or 1968 through the 1970 models and they are usually not fixable because parts for them (especially the controller in the right kick panel area are no longer available). Autotemp II systems are readily fixable because parts are available for them since Mercedes Benz bought the patent rights for the system and improved the quality of the controller. Because Mercedes Benz has a strong policy of supplying replacement parts for most all of their historic models, Performance Analysis Company still makes the controllers as new again that match the improved Mercedes systems, so we can get everything we need for these systems going forward. The Autotemp II plus systems that started with the formals in 1974 were quite problematic and parts availability for them is also an issue. So the 1971 - 1973 models are the only realistically fixable systems.
 
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I would just add that Autotemp 1 vehicles started as early as 1967 or 1968 through the 1970 models and they are usually not fixable because parts for them (especially the controller in the right kick panel area are no longer available). Autotemp II systems are readily fixable because parts are available for them since Mercedes Benz bought the patent rights for the system and improved the quality of the controller. Because Mercedes Benz has a strong policy of supplying replacement parts for most all of their historic models, Performance Analysis Company still makes the controllers as new again that match the improved Mercedes systems, so we can get everything we need for these systems going forward. The Autotemp II plus systems that started with the formals in 1974 were quite problemmatic and parts availability for them are also an issue. So the 1971 - 1973 models are the only realistically fixable systems.
The ATC II in the formals can be quite easily modified to a manual A/C.
 
I was asking because I had somebody asking me for a 67 imperial auto temp unit. They were asking if it was a auto temp 1 or 2?
I’m not sure how to tell?
Are A/T 1 and 2 both available on the same year/model?
 
I was asking because I had somebody asking me for a 67 imperial auto temp unit. They were asking if it was a auto temp 1 or 2?
I’m not sure how to tell?
Are A/T 1 and 2 both available on the same year/model?
No, Autotemp 1 only on 1967 through 1970 models, Autotemp II only on 1971-1973 models, and Autotemp II + on formals only 74 and up...................................
 
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Can someone briefly explain the auto temp 1-2 to me. I know there is a problem with them working?
One is more desirable than the other?
We’re both available on the same model?
What years did start producing auto temp and when did they stop?
I have AT1 in my 69 300. Is there a plan or info on bypassing the climate control system to just get heat and defrost? I don't intend on fixing a/c
 
The ATC II in the formals can be quite easily modified to a manual A/C.
Hi thethee! Can you explain or provide a link or links on converting the formals to manual A/C please? I love the formals but have never bought one because i live in a very hot environment and the A/C systems never worked on the cars I looked at. And everyone either said they're not fixable or VERY difficult to convert to manual.
Thank you!
 
One great thing with Autotemp I is that the controller, transducer etc is located in the right kick panel area INSIDE the car. This is a much better place than in the engine compartment.

If the system wont kick on, one reason for failure is vacuum leaks. Theres lots of vacuum hoses on the passenger side, just under the dash. The system also uses 2 vacuum reservoirs under the hood that can fail.

My Autotemp I system had bad hoses and someone had mixed all the hoses at the controller. But the controller, transducer and the rest was functional.

Heres the servo in action: https://www.ravjagarn.se/blogg/wp-content/uploads/controller.mov Movement when I turn the dial frm 65-85 and back again
 
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Well, I haven't been on the forum in a long long time so it took me a little while to respond.

The info on converting an autotemp formal into a manual A/C should be right here on the forum somewhere as I've personally succeeded in doing just that.

Let me see if I can track it down.
 
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