Are they both pressure switches or is one of them a temperature switch? They are both open circuit per my DVM (dryer off the car)

I set up a pressure test on the switches pic below. The switch with 2 wires never changed state (remained open circuit) with pressure up to 140 psi . The other switch with 2 spades on it closed at around 80 psi.

Does anyone have a link to an AC wiring diagram for an 83 W123?

Thanks in advance.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

One is a temp switch and the other is a pressure switch. The temp switch controlls the Aux fan, and the pressure switch controls the compressor clutch coil. My car has a high/low pressure switch so that the compressor is disabled if the pressure gets too high or too low.

I broke off the temp switch one time by over tightening it. It did not cause a freon leak though. The pressure switch has to be exposed to the freon flow, so when you remove it from the drier, it will cause a freon leak.

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RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

What temp does the temp switch trigger? I am going to use Envirosafe ES12A. I have one can already and just found a kit with 3 cans of ES12A for $20 It'll be much easier than going with R12 for me.

Should I use the same pressure and temp switch if I am going with ES12A or are there more optimal ones to use? I'll take a look at the Envirosafe site and see what they say.

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Can you give me the p/n of the hi/lo pressure switch? Seems like a good thing to have.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

I'm using Freeze-12 in my car. Junk? Maybe so, but it is working for me.

I do not know how hot the Freon gets before the Aux fan kicks in. The drier gets hot pretty quickly.

I would say that the OEM standard switches should be fine.

__________________
RRGrassi


70's Southern Pacific #5608 Fairmont A-4 MOW car

13 VW JSW 2.0 TDI 193K, Tuned with DPF and EGR Delete.

99 W210 E300 Turbo Diesel, chipped, DPF/Converter Delete. Still needs EGR Delete, 232K

90 Dodge D250 5.9 Cummins/5 speed. 400K

Gone and still missed...1982 w123 300D, 1991 w124 300D

I just fixed my A/C system in my W123, and I agree. The Freeze 12 cools okay compared to other R134a systems, but poorly compared to some R12 system temps I've seen forum members achieve. I'm considering taking my license test and getting some R12 up in there...

And yeah, the pressure switch works fine (at least with the Freeze 12).

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1982 240D 4spd, 327,000mi

I have the W123 A/C system wiring diagram. If you need it, PM me and I'll email it to you. I'm assuming your 83 has the Delco compressor. Automatic climate control or manual?

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1982 240D 4spd, 327,000mi