LED Lightbar Wiring Harness (prefab) not working, what am I doing wrong please?

[mtncrzr]

Simple LED Lightbar Wiring Harness (prefab) question: Jump Power(+) to Blue Wire?

In simple terms, to get the relay to close, do I need to jump the power (white) to the blue wire in the diagram below?
The kit did not come with a wiring diagram and I don't want to blow the relay.

I'm using a mictuning 300w Wiring Harness w/40Amp Relay.
The light bar works fine when wired direct to battery terminals (without harness).

I was going to use a foot switch, harkening back to the cars I grew up driving. So far, I tried jumping the black/white leads going to the switch, and leaving the blue alone. I thought the blue was just for an indicator lamp. But I'm pretty sure doing that just connects power to ground. The light bar did not switch on, and a lot of heat is produced fairly quickly in the jumper wire (naked steel wire). No fuse is blown. All as you would expect connecting power to ground.

Do I need to jump the power (white) over to the Blue wire to get that relay to close? If so, what is the ground wire (black) going to the switch for? Just for the indicator lamp? and it's not needed for a non-illuminated switch?

The 1 other thing is that I'm mounting the relay to the frame with the ground screw for the battery, somewhat temporary just to get it going as that was the easiest connection. can't see why that would be an immediate problem, car is running fine.

My voltmeter is missing at the moment so I have not been able to chase anything down. Is it safe to jump power to the blue wire? Thanks!

 

[DLM_2002]

Is there a fuse between the battery and the relay? by jumping the white and black in your drawing you would be creating a dead short B+ to B-

This is what it should look like as long as its a 4 pole relay

 

[mtncrzr]

Thanks DLM2002, your diagram seams to be 90 degrees off from my relay somehow. It's a prefab and I'm just trying to figure out how to wire the on/off switch. The relay came all assembled with wires, all I need to do is connect terminations.

So in your diagram, is the correct way to activate the relay to jump 87B (B+) over to 86S?

So I guess I need to jump the WHITE wire (B+) to the BLUE wire in my diagram, would that be a safe assumption? That seems the way to get control power to the relay, according to your diagram. That was my conclusion, but I don't want to blow the relay. I thought it's odd that it's a BLUE wire. Usually that color would be reserved for a secondary purpose. Seems it should have been red wire out to switch, maybe white wire back down to control.

So then the only reason for the ground wire at the switch is for an illuminated switch, correct? mine is not illuminated, I'm using a foot switch which I'm surprised I've not heard more people talk about. I'll be running lights on the rural highways, mounted on brush guard. It's just a pushbutton that I'll floor mount.

Would anyone know of a good way to test with a voltmeter to determine if that's correct or if it's a bad idea to do, to jump WHITE to BLUE at the on/off switch?

Thanks!

 

[85RedRunner]

You probably have 3 wires going to the in cab switch from the relay..

All you need is the blue one.

Then you pull power to the other terminal on the switch from 12v acc from somewhere inside the cab.

Or you can do it as you have pictured, just minus the ground wire.

All the switch does is power the relay.

(Very confusing how you have the 12v and ground "jumped" together....that should make some fireworks)

 

[85RedRunner]

 

[mtncrzr]

Thanks 85RedRunner, Yes, it's extremely simple. The white from the relay is 12V and needs to be connected to blue wire to power the lights.

These lights are amazing, best $40 I've ever spent. If I do a write up are people going to think I'm someone from the selling company? They are seriously a no brainer, assuming they last a while.