Wiring my electric fan, will this work?

[EMW150]

I have the Moroso switch panel that has a small led that just connects to the terminal on the toggle switch. Since this wire ties into the wire from the thermostatic switch to the relay, when the thermo switch energizes the relay it also energizes that side of the toggle switch and the led lights even though the switch is turned off. This way I can see exactly when the pump is coming on and when it's shutting off.

 

[hllon4whls]

What I was trying to say is, you cant take power from the battery to power the fan (constant hot side of the contacts) and take power from the same place for the relay coil and switch. As Michael Yount stated, you cant have them both running through the same ground either. This is the part of the diagram that really troubles me. You will have to run 10 ga. minimum wires to the switch if you go this way.

NOT.
Assuming you have the right diagram for the coil and power contacts for the relay, you can wire it just like the very first diagram and it will work. Just add one fuse for the fan and one for the relay.

As far as using the ground as a switching point, why not? Most of the OEM relay circuits in fords (and I assume all american cars) are ground switched.

I wired my car wp and fans up exactly like the first diagram (without the led) and all worked fine. I now have a painless wiring panel merely for the pretty boxes the switches and fuses come in. Still the painless only activates my relays but now with an + switch instead of a ground switch (only because I had to).

 

[EMW150]

Yeah, I missed that post. You wouldn't need to run 10 ga to the switch and you can use the same connection point. The tripper wire to the toggle switch is not going to draw the amps to operate the fan only enough to trip the relay which is not much at all. I have mine connected this way also.