1995 Jimmy starting trouble

I have a 1995 gmc jimmy 4.3L vin W and it has 97500 miles give or take on it. I have had the trans rebuilt and and it was running fine for a while every now and then I will have some trouble out of it. A month or so ago the truck started acting funny by funny I mean the abs lite would kick on and the it felt like the trans would gear down then it would be fine again after a few secs. When I go to start the truck I would turn the key and my dash board cluster lights would not kick on then after a 2 sec delay or long they would kick on and then the fuel pump would hummm and it would start well about a 2 weeks ago I was on my way to work and it just cut out so I shut the key off and turn it again and I have no dash lights so I waited and waited and still nothing. So I pushed it to a friends house and its were it is sitting now. But that weekend I started looking and I checked the fuses and the relay and nothing still. I tried to read for trouble codes and it wont connect to the computer so I figured that is what the problem is so I order one online took it to a dealer had it programmed and put it in after checking voltage to the computer so I wouldnt fry it out and connected the battery and still nothing no dash lights no fuel pump sounds. Im at a lose I dont know what to do now I check the grounds that I could get to and the ones I couldnt I dont know about them yet. Could I have a bad fuel pump but I figure if I do I would still have dash lights right? I dont know what to do can you help me out please