Wiring A/C and relay help needed

[Rebar]

Hi
I am not all that good with electrical and need some help getting my a/c connected, when I got the car some of the wiring was cut for some reason. It is a 85 euro with no front condenser, instead it has a rear left fender mounted condenser with a fan.

Here are some pictures showing the wires that are cut or disconnect that I am trying to figure how to reconnect.

The green wire goes to the compressor, I was not getting any voltage at the compressor and the clutch did not engage when I had the ac running.

There are 2 paired black wires coming out of the relay, one wire on the same spade seems to have been cut, and one black wire coming out of another spade on the terminal and I don't know where it goes. The red wire one the relay has an inline 25 a fuse and it seems to match a cut red wire on the #2 fuse in engine compartment.

There is a red wire coming off the white connect on the other relay next to the coil, it is not connected to anything. Finally there is a small black box with a black cut wire above the relay that is next to the coil.
Any ideas would be appreciated.

[kuehl]

Toss out what you got and start over.

1) You will need to trace the wire that turns on the compressor clutch and euro fender condenser fan. This wire will be from the AC thermostat in the cockpit and it will run to the back where the current relay is that you found.

2) You need a typical AC RELAY, 5 pin SPDT 12v, like what you have, if it works fine, if not get another at local auto parts store. To power the AC comp clutch and the small blower fans on the euro fender condenser box you will need 15 amps; 25-40 amp relays are common.

3) The wiring at the relay will be:

Terminal 30, power from your power source you choose in the engine compartment, such as tapping off the 3 fuse panel in the LH rear corner.
Put in an inline 20-25 max amp fuse

Terminal 85, body ground

Terminal 87, create a "Y" splitter wire to feed power to the AC comp clutch and the blower fans on the euro fender condenser; the fender condenser fan ground wires go to body ground. Put in an inline 15-20 max amp use on the wire to fender condenser fans.

Terminal 86, to AC thermostat in cockpit.

Use 14 gauge wire for terminals 30 and 85, 16 gauge for the others.

Test the fender condenser fans with power supply before you proceed.

Test the wire from the AC thermostat for power by turning its knob fully CW,
you should have power at full CW and no power at full CCW.

Test your AC comp clutch with separate power supply, negative to comp body and positive to its clutch wire, clutch should pull in when powered.

[silver911]

Great information for me too as I'm just starting to wire in my new A/C. I have a Sanden compressor but there's no hi/lo compressor safety switch, I think one should be installed so any suggestions?

[kuehl]

Yes. Before the compressor clutch

[silver911]

I've never installed one before, has someone posted info on how and where to install?
Thanks for your help.

[86 911 Targa]

Just refurbished our A/C system.


1. Remove the green wire which is attached to the compressor.

2. Connect the HI-LOW switch to the high side compressor fitting.

3. Attach one of the switch wires to the green A/C wire harness.

4. Attach the other switch wire to the factory green wire to the compressor.

Easy-peasy....

Good luck,

Gerry

pm me as needed.

[Rebar]

Thanks for all the help guys, really appreciate it. Will tackle it in the next few days and see if I can follow the great instructions