Chevrolet Repair: Truck wont start with new battery, chevy g20, test light

Question
Hi, I was driving and the truck just turned off. I tried restarting and it started right up but turned off again in about 2 mins. I had the battery tested and it was dead so I replaced with a new one. it drove fine for a day and a half and turned off again while driving. Will not start. I turn the key and it starts to crank and stops immediately without turning over. In the last month I've replaced fuel pump, starter and a ball joint and now the battery. I had the alternator and voltage regulator tested and they are fine.
The van was a custom van with everything removed except tv. Now interior lights do not work but they did before this problem. I'm thinking there is a short in the wiring or starter wires are touching. This is a an '89 Chevy G20. Any help will be greatly appreciated. Thanks, Doug

Answer
Hi Doug... well the easy test is go to the starter and test the small wire when you turn the key to start..it should light up with a test light....if you have power there on the key and you have power on the battery lead at the starter it should crank....if not check the solonid on the starter...if you don't have power ath the big post 12v constant check the wire.if you don't have power at the small wire when you turn key to start then check that wire also...they could be shorted up in the tube that comes down the back of the bloce above the starter...hope this helps