Battery? Or Cables?

I would have the battery tested and alternator tested also make sure the batter cable ends are clean and tight.

So does the battery drain without it running?

Once you guys get the battery drain solved, here's my standard reply to the idle problem:

Sounds like the battery might have been disconnected or run dead recently. If so, the Engine Computer lost its memory and has to relearn "minimum throttle" before it will know when it must be in control of idle speed. It also might not give you the normal "idle flare-up" to 1500 rpm when you start the engine. To meet the conditions for the relearn to take place, drive at highway speed with the engine warmed up, then coast for at least seven seconds without touching the brake or gas pedals.

Thanks for the input caradiodoc hope your mon is good one.

Your best bet is get a multimeter that can read amp draw and hook it up to your truck like the instructions on multimeter tell you and start pulling fuses one at a time till the draw goes away then you can narrow it down to what circuit it is.

Hold on a second. It doesn't dim the dome lights? That implies the battery voltage is fine, and is a dandy observation by the way that most people miss. What exactly is the symptom? A drain on the battery shouldn't kill it very quickly. It should take hours. Anything faster should be noticeable that something isn't turning off.

When you turn the ignition switch to "crank" do you get a single kind of loud clunk from the starter? If so, you likely have the little silver Nippendenso starter and it has worn solenoid contacts. It will crank if you cycle the ignition switch enough times.

So the battery isn't draining sound's like you have a connection or starter/starter solenoid issue.