Turned the truck on tonight - lights both came on for a split second then went off. Flicked them several times and they would come on for just a flicker.
Upon further analysis - the ballasts hiss for just 1 second - then pop-pop - then do nothing.
I switched them with each other and get the same result. Both ballasts do the hiss - pop-pop - thing.
These are SlimCubby ballasts. Headlights worked great for the past 1yr 3mo. Pissed and may need to look for a more reliable ballast.