Engine wont crank over why?

Was driving came to stop at red light when car shut off, no power at all no lights on dash or hazard lights. Have changed the fuel pump, the fuel filter, replaced the battery. The car will turn and sounds like it wants to start but never catches and starts. The lights on the dash do not light up either. Was thinking it might be the computer box or the electronic ignition. I am at a loss which way to go from here.

On a 3 prong ignition coil that fits a 99 chevy tahoe why is it that the pink wire is hot white wire hot and black and white wire hot when I turn the ignition on. Why does the pink wire make the other two hot?

My SUV was running great. Then I was driving and all of a sudden it shuts off mid drive, sudden loss of power then shut off. After sitting a few minutes it started again. But as soon as I hit the brakes it shuts off again. And again until I get it home replace the alternator that tested bad. And now it slowly turns over but not enough to start. Sometimes it clicks sometimes it turn over very slowly. So I took the starter and battery in both tested. The starter was bad so I replaced it and same problem occurs. I am not sure what I need to do. There are no engine light on. So any ideas?

Okay, I will check that first thing. I have been reading that a bad positive cable from the battery to the starter could also cause an issue. But I'll check it out and let you know! Thanks for the fast response.

My 1999 tahoe used to make a humming noise that came from the fule pump. It was starting fine in the morning but that same evening it would not turn over and also I do not hear the humming sound coming from the fule pump. I had the battery checked and it was ok. I also checked the fule pump relay and it looked fine. Could it be the fule pump?

Our tahoe will try to start but will not turn over completely. The lights work and the radio works. What could be the problem.

Truck had small, ineffective battery which sometimes my clock would be reset or if I tried to start too many times in too short a period would to start. Other day it would not start but was cranking, it would crank crank crank thunk. Turn key again, same thing. Almost started a few times. Ruined battery. Bought new full size battery and now get nothing, no crank or start. All inside lights work fine, radio etc, cleaned battery terminals, checked fuses, replaced ignition relay, all grounds are attached. Prior to this for three months I had a camshaft position error, (I think. It was cam-something) but it ran okay so did not worry about it. Is it possible I have fried the starter and if so, why am I not hearing a click? It is possible it is the original starter? Old but not too many miles on truck.