I'm brand new to posting, so adding a picture might be a bit much for me.
The dual pressure sensor is located on the front passenger side on the AC tube. It's right above the windshield washer filler. It's got a four pin connector. It has two fat wires, and two skinny wires. The two skinny wires are black. The solid black skinny wire is a ground. The black with white tracer (white line on insulation) is the lead that you would splice. There are easy splice devises at the auto parts store. Just use pliers to squeeze close over the wire once you've coaxed the wrapping tape of the harness back a bit. It's easier to manage with the connector removed from the sensor. The AC doesn't directly tell the fan to run. It's the fact that the compressor presurizes the line when it's on that closes the dual pressure switch (sensor). The computer then provides one of the several possible reasons to pull the fan relay in. There are two relays. The low speed has a resistor. The high speed relay applies battery right to the fan. It's not practicle to monkey with the high current side of the fan circuit. Instead, this mod uses the low current control signal approach to develop the "fan on" condition. The thermostat swap is sloppy, kills the grass, is tight for the hands to get down in there, but makes such an improvement. Size and get hose clamps ahead of time so you don't have to re-use the squeeze type originals. Get the rubber dounut gasket with the thermostat.
