I posted some of these pics on a FB group a while back. I finally got to tracing all the wires and removing this mess. General consensus states this was an aftermarket alarm? I thought maybe it was a ignition interlock attached to a breathalyzer as I found a GM pamphlet in the glovebox. There's also a hidden button (valet?) Most of this was tucked under the dash and the bigger wires were run through the firewall to under the hood, but disconnected, close to the fuse panel.

Good news is the car still starts and the remotes still work.

What do you all think?

 

FB is always right. Why ask us?
If I knew what wires the relay connect I could probably figure it out. Any numbers printed on the under side?

 

I see more experience from you guys than I have elsewhere. Anyways, there are no numbers printed on the box. The green and yellow went through the firewall by the fuse box. The black and red with the plastic crimp went to the red led. The black with the metal crimp was grounded the the metal frame and the orange and white wires were spliced into the ignition. Anyways, it all seems to work ok. Now to patch the hole in the firewall. Looks like it was beat with a hammer...

 

No numbers on the circuit board?

 

Well it has a relay

 

I went that far myself. It didn't really seem to help much.

 

unfortunately no.

 

It starts , it runs, it drives! Enjoy!

 

Truer words haven't been typed here in awhile.

Somebody was doing something for sure. Optional accessories good to get out of the way. Lighten the load.
I had similar thing with a van purchased at auction from municipality. It had alarm and wiring to headlights and so forth to flash them.
I never tried to figure it out just cut it out and wired back to original best I could and moved on.
Your guesses seem on track a DUI interlock device or alarm/remote start the good stuff taken out the residual left behind.

 

Breathalyzer lockouts are much more secure/tamper proof and professional.
Alarms don't hook up to the ignition switch.
The ignition switch does not provide power, it sends a digital signal.
Might be remote start, they don't normally have a LED and need something for the PK3, usually a spare key hidden under the trim. Needs an antenna.
I don't know what might connect to the other pins. Might be a serial port for programming, those usually use 4 pins.
Looks like the 2 larger wires are switched by the relay, not big enough for starter too big for power supply to the circuit.
Small red and black are normally power for after market things.
What wires did the orange and white connect to on the ignition?