Hi All,
I'm installing aircon in my 66 mustang that has a 98 DL LTD engine in it. (5.0)
I'm trying to connect a signal to the EEC so that it knows that the aircon is on -
Mainly to adjust idle and run the thermo fans

I've studied the wiring diagrams and as near as I can figure it applying +12 to pin 41 (Pink / Dark blue wire) should switch pin 69 to earth, that should allow me to engage the WAC relay, which in turn will engage the compressor clutch ( and signal pin 10 on the EEC)
Is this correct ? I cant for the life of me seem to get it to work.

I have found random bits on the net about needing the Evap sensor hooked up ( bit of a problem as it's long gone), and also references to the fan blower speed.
I have tried earthing these, connecting them to +5v, and connecting them to +12v but no joy.

Does anyone have any ideas -
Even the best way to bypass the EEC and engage the thermofans - but still leave them connected to the EEC so that it controls them off the Engine coolant Temp ?
Cheers
Dave

the compressor also wont engage if the pressure switch on the TX Valve isn't connected. Sorry I cant be of more help than that.

Gsb

The Evap Sensor is just a thermistor poked into the Evap core - using one of those also gets rid of the horrible Themo switch and leaves that part to ECU Control. Theyre a dime a dozen - used in all i6 EBII onwards, and all V8 EF onwards Easy to put in and does the job right.

Im not 100% sure about the blower speed - on some vehicles (didnt think on the falcons) it was important.

From pin 10, you need to go to your TX Valve pressure switch (Think you need one by law - but this is your pressure cutout switch). The other side of said Switch goes to your WAC Relay, and then off to the A/C

Nigel

So what Air con are you installing - std manual A/C, or a Climate control with sensors, adjustable temp, etc ??

Hi All - Solved the issue -
Hooked up a globe between the evap temp sender and earth -
Works a treat..
Thanks for all your help..
Cheers

Now - anyone know what the resistance values are for it, or where I can pick one up cheap ?