Spotlights = changed to different vehicle, won't work

Are you relying on an earth return?

If the bullbar is not well earthed or it is painted or powder coated the lamp housing may not be making contact with the frame.

cheers

A Multimeter is your best friend. You can buy a cheap one for about $20. They are not that hard to use for the unanitiated !

it was always quite straight forward once...all you did ...(as you most likely know) is to find the high beam at the headlights (usually always a + feed) and route through the dash switch to the relay.

These days some vehicles use a - switching for high beam...if yours does then maybe you have that issue?......and as a consequence you are switching / joining two negatives?...a friend had that very same problem last week on his vehicle...and after much brain scratching that was the issue.

maybe find the wire at the rear of the headlights and with your multi meter check that it is - or +........when activated

if so then a simple solution to re wire the relay accordingly......

that may help you

cheers

Take it to your local sparky!