according to diagrams the battery cable runs to the jump post then another cable runs from the jump post to the starter - can you start the car with your bench charged battery connected to jump post? - if so i'd say your problem is between the battery and jump post - you mentioned splicing wires somewhere - are the spices good? - also between battery and jump post there appears to be a large fuse - says it's down above the battery - also something called a battery sensor ..not sure what that does or if it must be reset after dead battery? - here's what i got
