Fan controller override questions.
 

Im going to be doing a electric fan conversion soon. I have the mishimoto fan setup and just ordered the fan controller .I plan on putting the sensor in the water neck and I want to hook up the override switch. The po took of the ac compressor off and the power steering pump is in its place now. Can you use the ac compressor harness as a override switch by turning the ac control on? Where does the harness for the compressor come from the main harness?

Sure, but it might not turn on the fan. Depends on what entity turns fan on in the first place. Also if it DOES turn on the fan, do you want the AC compressor running every time you do it, even during cold weather? imp

I read that as, someone removed the compressor.

No, you cannot use the A/C harness for the compressor because now, since there is no
compressor, that means no refrigerant in the system, and even with a compressor with
no refrigerant, it would not turn on.

You can ALWAYS wire a manual switch inside the car to over-ride the fan, and turn it
on. If your new fan is going to have a control relay, then you wire a switch from inside
to trigger the relay coil.

Diode isolate the trigger for the relay from the car source.
Wire the bypass switch tn the coil, in front of the diode.

https://cimg6.ibsrv.net/gimg/mustang...31e18d8086.jpg

Just a BASIC diagram, there will be a fuse in there for the fan's power... This just shows how
to hook up a bypass witch to the same fan relay the controller would use.

Very Nice! Now, what if it's a multiple-speed fan? :icon_bricks:
Just bein' facetious! imp

Then pick which side you want to bypass, hi or low.

Thanks.
 

Just wanted to use what was already there but looks like ill have to install a switch somewhere. The fan contoller comes with a green wire that I can use as the override will it still need a fuse?

IF you want a manual override, of course you will need to add a switch.
You can put like, a 1A fuse on the wire you're going to energize the coil manually with.