How to Correctly Install a Fan Override Switch

Can anyone give me the lowdown on how to do this correctly? Also, what temps do you all recommend turning the fan on at?

lost|concept wrote:

Can anyone give me the lowdown on how to do this correctly? Also, what temps do you all recommend turning the fan on at?

What Rhino do you have, 660 or 700?

700. Sorry should have specified.

I have not added this to mine yet ,but I thought you added the switch so say when you are in crawl mode or mudding heavy you can cut fans on manually an let run ,but your thermostat would still cut the fan on as normal . or am I wrong on this set-up in my head but if you were to cut fans on at a set temp I would think 180-200 to cut on

Yeah I want to be able to turn it on manually in certain situations, but I also want it to work as intended from factory. I will watch my aftermarket temp gauge and judge when to turn it on manually.

Um...

Someone on here has had to have installed a switch to override their fan. Everyone talks about doing it. Can someone please help me out on this?

lost|concept wrote:

Um...

Someone on here has had to have installed a switch to override their fan. Everyone talks about doing it. Can someone please help me out on this?

I have not composed a schematic to do a 700, but here is how you can do it very simply on a 660:



The 700 uses a relay, controlled by the ECU, to power the fan on and off. It would be a simple thing to over-ride the relay contacts with a bypass switch just like is shown above for the 660; just wire the bypass across the fan relay contacts instead of the thermoswitch shown in the schematic. You would want to use a switch rated at 20 Amps or more. Be aware that that fan power circuit is always hot (not controlled by the ignition key switch), so you would want to remember to shut it off, lest you drain the battery.

Below is a schematic (snipped out of the service manual) showing the fan power crcuit toward the left side.

Thanks Steve.

i just did mine today.. i installed a Diode in the harness between the t connection and the harness.. So when i applied 12volts to override fan it would not back feed the stock system..Works flawless!




So I made my connections before the fan plug near the battery box on my 660