I know which wires go to the wiper and can't test them at site where they connect at roof line to hatchback because fuse blows as soon as we turn on wiper. the short is somewheere between the cannect

there is a connector what connects to the wiper motor. Disconnect this, put in your fuse, then we can tell if it is a troubled motor. If it is troubled, you can juice it with twelve breakered volts (like from a small charger) and see if it is really shorting, or just needs to be hit with a hammer once or twice.

The wiring harness shorting might be a problem. These don't usually go bad by themselves but if caught or abraded by a heavy object can lose the insulation and start shorting. Really could not point you to this phenomenon as it hasn't come up for me. My wiring problems have always been opens, wires that don't seem to lead anywhere, etc...

hook a test lamp or a bulb in place of the fuse. it will go out when you find the problem. hook one wire to each of the fuse contacts .or you can use a buzzer. will shut off when problem is found. Easy