I replaced the marker lights on my 07 h2 and now all four corners wont light up. Any suggestions? Thank you

 

Replaced them with LED lights? Sometimes you need to reverse the polarity on LED's

 

Def try switching the bulbs around. Turn your lights on and test which position is correct

 

Be certain you have a good ground.

 

Also, if you bought a new set of lights on eBay that came with bulbs. Pull each one back off and get good bulbs. The 194 bulbs that come with eBay lights are often junk with tarnished wire contacts. You can scrape them with a razer blade, make sure the contact wires are straight and usually get them to work though but they also tend to not last as long either. All this is if that is what you used anyways...

 

I just replaced the interior festoon bulbs in my truck with some leds I got from amazon. They are very bright, and quality is good. The brand is siriusled