I installed my cathodes today. For power I used what I thought was the fog light cable. It was just hanging in there behind the dash. Everything works great until the headlights are on, then the power to the cathodes goes out. They work fine with just the driveing lights, but not with the headlights. Is this normal? Will tapping into the cig lighter fix my prob?

Thanks for any help!!

 

Try using a relay,

 

Yeah that'll do it, that wire always has power except when the low beams are on.