I had ordered them when I thought I was going to road race a lot more/when I didn't think I was going to be able to tune the car. Now that I'm going in a straight line, I'm less worried about pressure in the wheel wells in corners.
As @Mason said, it could be a fuse, or the charger you're trying to use is too fat/short. I have a handful of chargers that don't work, but the one for the RADAR detector did before I mirror-tapped it.