1983 911SC AC problems

[jbandbj914]

I just installed a new ac fan speed switch and now my compressor only engages when the switch is in the high position. Any ideas?

[jbandbj914]

Does anyone have a diagram of where the wires go with the new style switch?

[Bob Kontak]

Here is the 82SC wiring diagram.

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_82SC_AC.jpg

Give us some data. Why did you replace it? Did the compressor engage before on all three settings? Does the evap fan run? Does it speed up as you go from 1 to 2 to 3?

Maybe you have wires switched. I hope the new style switch has the terminal letters on it. Then you can see if you have a wiring issue. If the high speed fan wire and the temp switch wire were reversed I think the compressor would run only on the highest dial speed but I am not sure how the fan would function in speed one or two.

Please advise if you find a resolution.

[jbandbj914]

Thanks Bob,

The evap fan does run just fine. The fan switch changes the blower fan speed and you can hear the compressor turn off on the lower speeds. The old switch went bad and only had the lower 2 speeds but did engage in all 3. I'll post more as I dig into it more.

[jbandbj914]

I just looked and the new switch has numbers on it and not the letters like the old one. It is numbered 1 -5 so my guess is just follow the sequence?

[Bob Kontak]

The symptoms are similar but kind of backwards now.

How about the condenser fan in the front? It is on the same "wire" as the compressor clutch. I am guessing when the clutch engages in position 3 the condenser fan starts blowing as well?

If you have a multi meter you can figure out what terminals are LMH because B and C will be connected inside the switch in all three positions and then just one of the LM or H terminals will connect as you go through the speeds.

[jbandbj914]

found another post from 2003 that was very helpful!

a/c fan switch wiring help

It worked perfect on my car

[Bob Kontak]

So all is well?

[jbandbj914]

Yep everything is working quite well!

Thanks,
Jeff