where should i start looking for the solution to this issue?

this morning the van wouldnt start. i turn the the key on run position and it wont even crank over. i turned the key on the on position and jumped the starter thinking the starter was locked up to make it run or loosen it with banging on it while supplying it with voltage. i also noticed that the shift indicator light was not responding to the shifter position. i looked on top of the transmission and just before looking further down i see that battery acid has fallen on top of a big wiring harness. i wonder if that could be that problem?