First off, I just want to say I'm new to the forum and relatively new to auto repair so please forgive my lack of knowledge!
Well one day driving home my Suburban died on me immediately after coming out of a right hand turn. The engine began to smoke at the front passenger side near the lights, my hazard indicator lights, all running lamps, and all courtesy lights were stuck on and it wouldn't turn over.
To make a very long story short, there was a direct short in the pos battery cable (split on the frame) running to the solenoid. This caused a load of electrical damage, all of which I was able to repair minus a couple of unimportant features.
I have repaired and replaced everything to the point that when I turn the key to run/start, EVERYTHING comes on except I don't hear any click from the new solenoid, all I'm hearing is a high pitched humm or whine and it won't turn over. I replaced the battery cables initially which lead to my breaking the solenoid and replacing that as well. I also replaced the ground from the neg battery cable to chassis and the ground for the lamps.
HOWEVER, there was one thing I came across that i have yet to figure out. Near the solenoid there were 2 ground straps meeting at a bolt on the frame. I was able to find where 1 of the 2 lead to. It was at a point of which I believe to be a firewall?? underneath several hoses that seem to be part of a cooling system. Since I've re-grounded at that location and the one i found on the frame, I'm not really sure what the other strap leads to or what I should do with it!? Since I am unsure, I attached it to a piece of the body following the service bulletin released for proper grounding.
Did I do the right thing? AND PLEASE, ANY OPINION AS TO WHY IT WONT START AND WHAT THE WHINE SOUND IS???

 

If the whine sounds like it's coming from the rear of the vehicle, then I'd say fuel pump.

 

Or the starter motor running and the solenoid is not engaging.

 

So the whine was the solenoid engaging but starter motor was bad. So I replaced it. Also, I found where the shorts originated. One was on the drivers side wheel. The ABS speed sensor wires (connection in metal disc thing inside wheel) snapped during the turn. Also, the last mechanic cut the pos battery cable too short when installing new terminals making it so tight that it cut on the frame. I replaced all of the battery cables, replaced all easily accessible grounds and she started up wIthout hesitation!