tech question
 

got a question yesterday i was installing a cd player in my 94 pick up and i had the radio on for about 3 hours so i think i might have killed the batt but when i have ignition turned to the on position its showing the battery has more than half energy on the gauges but when i try to crnk it over it make a wierd noise but dont turn over. i also disconnected the wire that runs from the positive side of the batt to the fuse box then i re connected it, when i jump start the truck it starts no problem. anyone got any suggestions?

Your battery is dead. Pretty simple.

If your battery was already weak, leaving the radio on for 3 hours didn't help it. It may have a dead cell, meaning it is weaker than what its rated for.

Weak battery. Assuming you were running ONLY the deck (no amps, etc) a good battery should lat a lot longer than three hours and still crank the engine. The fact that it jumped easy screams weak battery as well. To confirm, have it tested, but I have a feeling you're due for a new one.

Clean your cables and connections while your at it.

Jump it, drive it around for 10-15 minutes. Turn it off, and see if it starts.

i did jump it and try to start it but it didnt start after i shut it off and the lady who sold it to me said it was a new batt. and why is my gauge saying that i have more than half a charge?

Since the gauge goes to 18, half a charge is only 9 volts ;)

If you battery is at anything lower than 12 volts, you have a problem.

And define "New battery" Brand new she got from a store with paperwork to prove? Or new to the truck, and she pulled it from her 1946 Buick she had sitting in the weeds for 10 years. I never trust anyone who says "new parts installed" unless they have receipts to prove it.

just yank the batt, go to the auto parts store and have them check it. Problem solved.

It's not an amp-hour gauge... it's a voltage gauge. 12 volts is normal. If you're down to 9 or 10 volts, the battery is technically considered drained, and typically will not be able to crank your starter.

autozone, advanced auto, etc all will check your battery for free...go get it checked.