Install Problem please help

How long. Where is it mounted. What make/model of truck?

What do you mean by "will not work"? Are you checking the SWR? Some common mistakes: the plastic washer on the antenna mount is in the wrong place. (it happens) Bad coax. Are you using the factory stuff that came in the truck? You can have a good enough "electrical ground" to lite a city, and still not have a good rf ground...which will result in a high SWR reading. A wire run from the antenna mount to the frame, if over a couple feet in length, can act as a radiator causing your signal to run down that wire instead of up the antenna. (so to speak) If you have a bad rf ground you have to "bond" the area where the antenna is mounted to the rest of the metal on the vehicle. You want to use flat braided bonding straps ideally, or large gauge multi strand wire, or even a piece of coax. You run this in short spans. i.e. antenna mount to door, door to body, body to frame. And after you do all that you still might not get the results you want on these new model trucks. (sorry, but now I will be away from the puter until this evening....) There are a lot of threads on here about your problem. You might get lucky if you do a little searching.

http://www.skipshooterantennas.com/ The best fiberglass antenna on the market, IMHO.