Howdy all,
So on my 1985 IROC 5.0L TPI, there is this purple wire coming out of the wire harness that runs out of the firewall just above/behind the brake booster on driver side, and the P/O put some kind of jumper on the factory plug, to close the loop. From what I found in the wiring pages is that purple is blower motor. Funny thing is my single coolant fan runs constant, so not sure if they have anything to do with each other or not...

 

If you search C100, you'll probably figure it out.

That's the service manual number for the driver side wiring connector.

https://www.thirdgen.org/forums/v6/454985-stumped.html Post 11 has a diag. that says purple goes to Starting system, or Wiper washer.

Owning the service manuals to your car is a really good idea.

 

only purple wire on that side that I know of is the starter wire. It's not supposed to have a connector on it like that though. pull the jumper and if the starter doesn't do anything then that's it. Starter wires is a 12ga (possibly 10ga) wire

 

I guess the advantage to that jumper if it is the starter wire, if you pull it, then likely no one is going to steal your ride. They'll think it's something more complicated to get it to run lol