1987 944 AC Problem

[Boz]

I have a 87 944 that keeps blowing the heater ac fuse. I have had this problem for a while but forgot about it over the winter. I have unplugged the Compressor and replaced the relay and it still blows the fuse right when the key is turned on. If I remove the ac relay the heater works fine and doesn't blow the fuse.. Is there a known place where wires like to rub through on them? It really has me boggled. Thanks

[Boz]

I have also tried unplugging the cooling fans but still no luck.

[mikepellegrini]

If you unplug the wire at the compressor, does it still blow fuses?

Or another way to test it is with the car off, remove the wire from the compressor and check with a continuity tester. That'll tell you if the curcuit is grounded.

If it is shorted out (and the problem is not in the compressor clutch) then I'd inspect the end of the wire near the compressor. That's the only place I can imagine where the wire would be shorting out. The rest of the wire is probably buried in a harness and is virtually inaccessible.

If you're unable to locate the place where the wire is shorted out, then your last option is to wire around it.

[kuehl]

There is some information here for common troubleshooting
of the compressor:
http://www.griffiths.com/achelp/achelp2.html