On the 85 300 D I have here is where I am at:

When I turn on the A/C at the climate control I have NO power at the 2 wires that go to the low pressure switch on the drier.

I have verified that my push button climate control unit is good. I swapped mine to another 85 that has working air and it works on his car.

I also swapped my Klima relay on the same car and it is good also.

I checked the micro cutout switch and it is not stuck or showing contact via multimeter when not pressed.

I disconnected the temp sensor in the head and it has not effect on the A/C.

Independent power to the compressor clutch activates it just fine.

What am I missing????

When the climate control unit calls for A/C is there some other relay or switch that it must pass through before it gets to the low pressure switch??

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1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
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