switch wiring

[loue]

Hello All,
Long time lurker that's taken a ton away from the forum. Long story short, I was able to wire my switch for my bumper mounted light bar and everything works great. Took a friend out to see the switch housing that i dremeled below the open cubby we have on bench seat radio bezel and realized my switch had been on for the past 8 hours... it was extremely hot.

Obviously the power is on when the truck is in the off position and I am trying ot figure out how to wire it so it's only on when the truck is on.

I use an amazon wiring harness below. Can someone give me an ELI 5 of how to run this to the fuse so the switch only functions when the truck is on? Below is the diagram and relay it comes with.

 

[RedFalcon]

The way I wire up my relays is pin 85 is a ground. 30 is power from the battery. 87 sends power to accessory (lightbar in this case). And I treat pin 86 as the trigger.
So on a typical switch you have power in (also referred to as led), power out (typically load) and ground.

In your case, since you only want the switch to come on when the truck is on, you need to find an accessory power source for your switch. An easy way is to use an Add a Fuse and tap into something nonessential in the truck. I usually use my 12v cigarette lighter. You could also just find that wire and splice into it using an inline wire tap.

So you have power into your switch this way. Ground out the switch like normal and send power out from the switch to pin 86 on the relay.

This wouldn't be too hard to accomplish with the existing wiring harness you have. All you would need to do is cut the wire feeding into the switch (and cap/tape off the end coming from the rest of the harness) and wire up power from your accessory source into the switch and everything should work.
Personally I prefer to make my own harness though and if you have a relay, it's really not that difficult. You just need wire and some connectors which you can get all of for less than $20 from harbor freight if you don't have it lying around.

 

[loue]

appreciate the response... I guess i need to explained like im 5... the response is very thorough, but seems theoretical as i read it...

Base on the wiring diagram i posted am i cutting the the red wire or the grey wire, capping it as you mentioned and tieing from the switch into the cig lighter? I'm aware red is clearly power, but I am under the impression the white is signal and thus would activate the switch, which i guess maybe why i am confused.

I also could just be dumb and over thinking!

Either way ty again.

 

[RedFalcon]

Sorry, I pretty much ignored the wiring diagram and just explained it in general.

With what you have, I would cut the red wire between the plug/connector and the switch itself. Then cap off the part of the red wire that is coming from the plug/connector. Then using either an Add-a-fuse or an inline wire tap, I would connect a wire from the cig lighter to the part of the red wire left that's attached to the switch.

The white wire is the signal wire, but it's a signal from the switch to the relay. The switch is basically just a broken circuit until you "activate" (flip/toggle/etc) it and then the circuit is complete. Once it's complete, it sends a signal to the relay.
The switch needs power (which it currently always has) and once you flip the switch, it sends a signal to the relay. This acts like a trigger and tells the relay to pull power from the battery and send power to the accessory (light bar). Hopefully this last little part makes sense and helps clear up the confusion about the signal wire.

 

[loue]

got it - makes MUCH more sense... really appreciate it!

So, cut red wire between switch and connector, cap off connector side, tap into cig lighter with switch side. perfect! i'll hit the hardware store tommorrow and get the inline fuse or tap and give it a go! thanks again.

 

[RedFalcon]

That should do it to make the switch and lightbar only work when the truck is on.