Fan Override switch help

[rvanstory]

Electrical is my achilles heel in this build and I need help. I installed a fan override switch on the dash so I can manually turn on the fan even if engine temps haven't triggered it. Here is the push button I purchased and installed in the dash.

https://www.amazon.com/gp/product/B0BYMBRGHK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

Here's the problem... the Ron Francis wiring harness has 2 green "sense" wires that go into a relay to provide power to the fan. That sense wire is one that should switch to ground (not 12v power) to trigger the relay. Here's a wire diagram for the switch. I want it to function like the one in the red box.

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I want it to trigger the fan relay AND I want the LED light to illuminate in the dash. I cannot figure out if this switch can accomplish what I want.

Is there a way to wire this switch so it goes to ground when pressed and will still turn on a light? If not, what switch could work to give me the same functionality? (switch to ground AND turn on a light)

[michael everson]

I think you can use diagram one but make the led 12volt live all the time. Then put the green wire on the top as well as the right side ground wire. attach the lower output to ground.
Mike

[topherchrisb]

Yeah I think what ME said is correct. It's easier for me to think of it as two separate circuits. The middle white section is for the switching control while the outside terminals in the blue section are for the LED. What's confusing to me is the polarity is different on the LED wiring between the diagrams... but maybe the have some fancy switching inside the unit? A simple test with a 9v battery should tell you if you can wire the LED in either direction... but one is likely more efficient I imagine. So setup your switch to close the fan ground when latched... then bind into the same wire that is switched to ground for the LED ground. In your desired path diagram they are essentially using the 12v from the device feed of the switch to power the LED. You're just going to now provide a ground to the LED dynamically instead.

[rvanstory]

Thank you guys for your responses!!! Now it makes MUCH more sense!!

[Jhinkemeyer]

As others have noted the manufacturer is inconsistent on the polarity of the LED in those schematics. In general in an LED polarity matters, so worth checking I imagine?

If it were me I would wire it like this. Battery positive to the (+) of the LED connection (constant).

RF green trigger wire to the common terminal (bottom most of the 3 center terminals). Connect the LED (-) to this RF green wire either at the terminal or otherwise.

Wire from the normally open (NO) contact (center contact in the middle) to ground. Activating the switch will make the connection of both the RF and LED to ground, completing the lighting circuit and triggering the fan relay.

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Edit: I think that with this setup as I mocked up the LED would come on when the fan kicked on from the coolant temp switch as well (as I think that the (2) trigger wires tie together back in the RF harness). Don't have time to dig deeper right now, but that may be desirable (indicating a general "fan energized" condition)? If not you'll have to get a bit more creative!

[cv2065]

This might help you out as well. Looks like the same button.

https://www.youtube.com/watch?v=XtqsLpDjZx0