did you try pulling the plug out the bics and checking for corrision or wire burnt out inside the rubber coating at the box plug------I would check to see if voltage is making it to the coil , if it doesn't andyou really need to dump the load and keep working I would take one of them blue wire splicers that you can squeeze over the wire and tap into the wire coming off the coil and run the other end to a voltage source that is only hot when the ignition is on and it should by pass the bics box as far as the tilt and boom lock out goes , it will still code up but operate ----- if you have a bics and it has seat and seat bar on it then I would upgrade to the newer bics box seat sensor elimination kit , if it is still available for that old a machine , which by passes the seat sensor ------