So it's been a few months since I've acquired Trans AM #2. This one is a 1986
305 NON-HO car. Carb/Auto. Very clean, but needs mechanical help. I'm currently cleaning up some wiring issues and I've encountered 3 plugs I can't quite identify, even with the help of the FSM.

#1. The first is yellow and purple. Someone put a jumper in it so it will crank in any gear. Removing the jumper will prevent cranking. The other end of the wires are connected to the trans range sensor. Looks like they have continuity.
What is this supposed to plug into? The only clue I had from the FSM was a clutch safety switch. This car looks like it was born an automatic, so not sure why it would have a plug for a clutch safety switch. I'd like to get it back to stock (read:safe). It reaches to roughly the steering column. Looking around, I didn't see anything it could plug into.



Any ideas?


#2. This is more a curiousity thing. A brown and brown white wire connected by a diode near the previously mentioned wire. Looks unaltered from stock, but no idea what it's for. I'll keep combing the FSM, but if someone knows...




#3. Purple/white wire. Per the FSM, this appears to be a crank signal for an EFI car. Not sure why a carbed VIN H car would have it, but I assume that they consolidated certain parts of the wiring to save money. It's not connected to anything, of course. Safe assumption? LOL




Thanks in advance for any help!

 

Purple/yellow neutral safety switch at the clutch pedal.

Diode, beats me but it's normal. Put a piece of black duct tape back around it like it was, and leave it be.

Last one looks a lot like the wire to the rear defroster. Check your shop manual for that wiring diagram and see if it matches up.

 

That's what I thought, but why on earth would an automatic car have a clutch switch? It's possible that it was a manual car, but I can't find any evidence of a swap. All the wiring for the automatic is in place. Strange.



Not sure why the tape was removed. Thanks for the suggestion.



I'll check that section. Thanks!

 

Same reason my T5 car has wires for the TCC on the brake switch and some for cruise and Bose radio, even tho it wasn't optioned for it. They used the same harness for all similar cars, just cheaper for production. You'll find numerous connectors that don't plug into anything. Cars with that option would have a module or another harness that plugs in there.

 

Makes sense. The plug has a jumper in it. I'm thinking there's a problem with the range sensor and the previous owner didn't address the issue.

Thanks!

 

That diode may be for isolation of the potential residual AC from the alternator. See sheet 134 in the service manual electrical diagrams.

 

Yup. Right on the money. Thanks!