Auto-Temp I & II

Some jerk had a vision and carried it out and with a test car must have convinced a chief engineer that the system was really ingenious - then the green light was given for it to go into production.
And then Mercedes bought it.
Not ATC II, which had already started, but the original ATC.
I'll never figure that one out.
 
And then Mercedes bought it.
Not ATC II, which had already started, but the original ATC.
I'll never figure that one out.
i have never heard that Mercedes bought the rights to the first ATC system, only ATCII which was an OK system except for the bakelite plastic housings that cracked after just two years. Mercedes made the housings out of aluminum so they didn't have those problems at least.
Are you sure about Mercedes buying the rights to ATC1 Stan and if so, do you recall where you saw that claim written up?
 
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My friend figured out what do the different positions in the servo do. They are marked in the picture.

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It started to look like there's a vacuum leak still somwhere, as the Auto positions started to work when I manually (well orally really...) sucked the vacuum to the main switch. Problem was that in order to try and find the leak(s) I should have the car running, but it was winter time so I'd had to work in freezing outdoors or get complaints of fumes getting in our house even if I keep the garage door wide open. Also my car has loud pipes, which of course save lives but on the other hand make finding vacuum leaks much more difficult.

So needed to make a special arrangement: hot water from a garden hose into the heater, vacuum from a separate compressor (of an old refrigerator) and power from the car's own battery. Also had a voltmeter reading the voltage from the blower wires.

Well darn, the bush button dial which I believed to be OK with 99% certainty, still had a hissing noise (not so obvious anymore, it was overrun by the car's running noise). But the Def position - which worked as it should - was silent. There are reproduction ones available so I ordered one and am hoping this will be the last fault in the heating. AC and rear heating need to wait a while, I need to get to driving in the mean time.

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While having the control unit open, I made a video of how the servo reacts to different adjustments of the push button dial and the thumbwheel. I hope you and the Mopar gods can forgive me saying "Chrysler Imperial". :rolleyes: As an introvert person it's always difficult to make a video let alone in a foreign language, so mistakes are bound to happen.

 
i have never heard that Mercedes bought the rights to the first ATC system, only ATCII which was an OK system except for the bakelite plastic housings that cracked after just two years. Mercedes made the housings out of aluminum so they didn't have those problems at least.
Are you sure about Mercedes buying the rights to ATC1 Stan and if so, do you recall where you saw that claim written up?
You are most likely to be right.
I would trust your memory far more than mine.
Perhaps I was thinking Mercedes bought the rights to "ATC II 1.0" while Chrysler already introduced "ATC II 2.0" (as how I try to describe the difference)?

The point being... Mercedes bought into it, lol.
Thanks, Steve.
 
The valve block I ordered was probably not for C-body. Looks the same but at least the electrical connections work differently than the original. So one more attempt to fix the original one. I did use some grease on the valve mechanism earlier, but apparently not enough. So now a more generous amount of silicone grease. And also replaced the original rivets with small screws to ease the next service...

Now it works as it should other than after startup neither of the Auto work before going into either of the Def positions for a while. Well, good enough at the moment.

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The valve block I ordered was probably not for C-body. Looks the same but at least the electrical connections work differently than the original. So one more attempt to fix the original one. I did use some grease on the valve mechanism earlier, but apparently not enough. So now a more generous amount of silicone grease. And also replaced the original rivets with small screws to ease the next service...

Now it works as it should other than after startup neither of the Auto work before going into either of the Def positions for a while. Well, good enough at the moment.

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Good work.

I had ordered the mode control switch from Jegs.

OER 3895790: AC/Heater Control Switch 1960-1974 Mopar A/B/E-Body - JEGS High Performance

They have one left?

I plugged it in and it worked for Shamu, my 1969 Plymouth Fury III convertible.
 
Mine is the same, but from eBay. It might work I guess but I didn't even try as the electrical connections connected differently compared to the old one. And it says A/B/E.
My bet is that they are all the same.
That is, if the vehicle came with manually controlled air conditioning.

The electrical function is fairly straightforward.
Three contacts on one side that sends power to the air conditioning clutch directly for max AC and AC, or the other contact is sent to a time delay relay for dehumidification in heat and defrost modes (for a period of time).
 
So that's the problem, Auto-Temp is not a manually controlled air conditioning.
You are correct in that Autotemp is not = manual control.

I guess I don’t know what you are trying to do, for sure.

Are you trying to insert a manual control switch into a set of autotemp devices (actuators, AC clutch, blower)?
 
Just trying to make the Auto-Temp work. And now it does except for the cooling. My previous messages are trying to explain that.
 
Ok
I’ll look at the FSM. If I have any suggestions, I’ll reply. I’m curious too…
Have you inspected the ‘cam’ mica grooved pieces that move the vacuum and electrical switch actuators inside the mode control switch?

When I took my mode control switch apart, there was obvious wear on the angled cuts that move the mica pieces, which have tabs on them to physically slide the rubber seal and a plate for the electrical switching.

Here’s a picture of the good ones and bad (second). Note the worn edges on the second bad piece as well as the 4th bad one.


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Have you inspected the ‘cam’ mica grooved pieces that move the vacuum and electrical switch actuators inside the mode control switch?
Yes I have, they're ok. At least they looked intact and there were no loose parts. First thing to do with the AC is to check the system for leaks and recharge. But at the moment I'm quite happy with working heater already compared to earlier state.

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