Truck Repair: truck wont start, amp fuses, wire weather

Question
I have a 99 International Tractor with a Cummins N 14 Engine.It was parked for about a month not used but started and idled once a week for about 30 minutes.It was used periodically about 1000 miles a month prior to being parked.
Now it won't start,first the ground cable from the batteries to the frame melted (the Bolt)cleaned up and replaced batteries but still won't fire.It will turn over,that's it.No smoke from the stack either when turning over.
Any suggestions?

Answer
Check the fuses near the starter for the ECM & wiring too.Navistar is the only OEM that refused to put unswitched battery power wires to the batteries,they hook them to the starter causing a 434 fault(low battery voltage) when you crank them.The wires are two purple POS wires to POS terminal on starter & a ground either to the block or NEG post on starter.The unswitched battery harness is a 3 wire weather pak connector,the 2 purple wirew on the outside & ground in the middle.There are 2 15 amp fuses in the Cummins harness.