How to put a switch in Nelson 3-Relay harness?
07-22-2010, 08:54 PM
#1
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How to put a switch in Nelson 3-Relay harness?
I want to put a switch in my cab so i can manually turn my fans on constant. Anybody have a diagram of how to do this?
07-23-2010, 09:08 AM
#3
if you're wanting high speed at the command of a switch . . .
Get a 12v diode and place it infront of the A/C tap wire. The diode is so that the compressor will not run when you hit the switch.
07-23-2010, 09:24 AM
#4
If you have the 2 pin type harness this will work,
Up is low, middle is auto, down is high. If you have the single pin and AC harness, then I think if you replace the high in my diagram with the ac it should work, but use a diode like tootall said.
Up is low, middle is auto, down is high. If you have the single pin and AC harness, then I think if you replace the high in my diagram with the ac it should work, but use a diode like tootall said.
07-25-2010, 10:41 AM
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I do have the single pin harness. Does that mean that the fans wont have both speeds? Is the switch in the diagram a 3 stage switch? I just want a simple on/off switch to turn both fans on high for when its 100+ deg, on a dyno, etc. Mainly so i can get the fans on ahead of time before i put it on a dyno and still have them work.
07-25-2010, 10:45 AM
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Also, should i splice the wires and then put the diode between the splice and the switch? Will I need a diode for both wires? Sorry for all the questions but I know nothing about wiring lol
