HELP: Electrical Problems

[jeffbo]

Not really sure where to post electrical problems, so I guess I'll just do it here. Anyway, I can't get my truck to start today. I was having electrical problems last week. I would attempt to start my truck and there was nothing at all. No click from the starter and the dome light wouldn't even light up at all, as if there was no power at all. I messed with the battery connections a little and my dome light would come on, but as soon as I turned the key the dome light went out and nothing happened again. So I repeated the process, jiggling the battery cables until my dome light came on and turning the key. Eventually I got it to start after a dozen tries. Drove to the parts store and picked up a new negative battery cable, assuming it was the problem. Installed the cable and the dome light came on instantly, a good sign. Turned the key and nothing. Messed with the new cable some until the dome light came back on, turned the key and she started. So I figured it was the battery, since it was old anyway. I installed a new battery and everything seemed fine. The truck worked perfect all weekend for me. Then today, I drove to work. After work I went to start it and the starter clicked once, the dome light died, and that was it. It is doing the exact same thing as before. I attempted to jump start it and that didn't work. Something I noticed today that I didn't last week is that while I was sitting in the truck with the door open attempting to start it, the dome light slowly comes back on within about 1 minute after turning the key. Once I turn the key it immediatly goes out. After I release the key I watched the dome light and it just faintly glows and slowly gets stronger, like it is gaining power. If I turn on something electrical, such as the headlights, the dome light goes out, but the headlights still won't come on. It's like they don't have enough power. I hope this makes some sense to you guys, kind of hard to explain it. So any suggestions? All I can come up with right now is possibly the starter solenoid. Would it cause the truck to do this? I'm going to try to test it with a test light ASAP. How do I go about this. Do I just connect the light to the 2 posts on the solenoid and have someone turn the key or what? Or could the problem be something else? I just hope it's not a short somewhere in my wiring harness. I would appreciate any suggestions. Thanks.