You should be able to pull the whole rubber grommet through the firewall so you can examine the wires and see what got cut or shorted (gonna have to be done anyway)...the wires should pull through the grommet easily once it's pried out of the pass-through hole and you'll be able to see what happened. I do it with the battery disconnected in case anything else is set to short.
That's not the worst I've heard. Worst was me trying to do a cooling system flush in the shop, found where I wanted to cut into the heater hose the install the flush tee, turned around and got my super sharp hose cutter outta the tool box.
When I cut, there was a huge flash of blue light and a loud crack. I realized this was unusual for a heater hose
...then I saw what happened...
The heater hose was wrapped in the same black split-loom plastic as the wiring harness...when I'd turned back around, I grabbed what I thought was the hose I was looking at before, but it was actually the harness, which I just cut in two. runaround Time to panic...
Had to buy and install a new harness and battery cable (also ran through there)...added three unpaid hours onto an already too long and hot day...inform the customer that I'm a spastic baboon and screwed their car up, now I'm fixing it
, etc...
Feel better?
