Not sure where to post this but i found out something today when working on my car lights.

I have a pair of BAJA design squadron R lights and when i use it with the provided switch, my lights are noticeably brighter.

When i hooked this light to use with an Air On Board switch, the light are dimmer. Both uses the same fuse. Not sure why.

This is what the specs on BAJA lights
-----------------------------------------
Squadron-R Pro, Pair Wide Cornering, Amber
Wattage/Amps: 40W / 2.90A
Lumens: 4,900 Utilizing 4 Cree LEDs


Air On Board switch
--------------
AIR ON BOARD
12 VOLT
3 AMP


uses a 15 AMP fuse.

Anyone with electrical knowledge please chime in and explain to us why in detail.. I don't want to spend money buying a switch that would make my lights dimmer.

Resistance. If the switch adds any resistance to the circuit then the voltage to the lights will be lower and so will the brightness.

If you have an ohm meter you can measure across the switch contacts and compare.

No relay?

If the operating current is moving though the switch… then you would be subject to resistance & voltage drop associated with it.

That said, if the operating current is passing through a relay, the switch would have zero effect on your lighting output.

Another thing to note… if you are using passing the current though the switch, your switch is now the fuse, not your 15A fuse. Check the switch for heat. I don’t know what the lights draw, but if you are exceeding the current rating, it’s only a matter of time until you have a melted mess to deal with.

This is the real question.

I'm guessing no.

Just replying to give a layman's explanation to why this is happening...

Yeah pretty much your switch has a higher electrical resistance than the one provided with the lights, it's acting as a load, i.e. it is consuming power. Your light is also a load because it also consumes power. Putting more than one load in series configuration drops the amount of voltage that other loads can use. Your switch is sapping voltage in the circuit, and the amount of voltage that your lights can use is now lower and as a result they are dim.

You can avoid this by putting your light and switch in parallel configuration: Using a relay.

It's more work but you get more life out of your switch too.

And possibly not cause a fire if you switch is not rated for it.

2 lights that draw 2.90A each = 5.8A and your switch is rated 3A, again assuming you are not using a relay.
It's that simple.

google Ohm's Law

and multiply the light ratings x2
like foudwd1 said

the wiring your use will also impact the lights.

you spent a bunch of money on quality lights, why cheap out on a crap switch??

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