LED's not working

[Moeggenpar]

Hi, I just installed LED tail lights with a new harness, also switched to a LED flasher. The tail lights flicker once when I turn the head lights on. The marker lights don't come on either. Maybe a grounding or fuse issue? I have new bulbs all the way around. Thanks for any info

[Moeggenpar]

it's a 68'

[A383Wing]

put the stock bulbs back in and see what happens....then report back

[WHITE AND RED 69]

Did you replace both flasher units or just one?

[Moeggenpar]

put the stock bulbs back in and see what happens....then report back

The stock bulbs didn't work either, it turned out to be a blown fuse. The tail and brake lights work, but the front marker lights do not. I replaced the front light harness and have power to the marker lights. Could the marker light housing not be grounded, or some other grounding issue? thanks again     

[Highbanked Hauler]

Run a ground wire from the battery to the light housing to make sure its grounded. In dealing with these cars make up a LONG wire with gator clips as you will have a need for one. I still use mine regularly  
As Red and White said there are 2 flashers, one for signals and the other for 4 way flashers  so you might have changed the wrong one ..