MONTE CARLO Check Engine light

[Alain]

Hello. I'm restoring the dash of my MonteCarlo 81. There is a light for the "Check Engine", but behind my dash there is no terminal (for the check engine line) on the connector that connects the dash to the fuse box. So, i'd like to know how does the "Check Engine light" works, and if there is a sensor that make it work when a problem is detected in the engine. My car doesn't came with CCC, or computer module, so i'd like to know what the "Check Engine light" was tracking on that model of Montecarlo, and what do I need to do to make it work.
Also i'd like to know about the speed sensor that appears on the pic. Where do i have to connect it?
And my last question is about the seat belt light. Also there is no terminal in the connector. Could someone explain me the wiring?

 

[pontiacgp]

if you have no computer and the check engine light is on remove the bulb

 

[pagrunt]

Non-computer cars used the same dash bezel as the computer cars so they all will have a filtered lense for the Check Engine warning light. GM is cheap so it is cheaper for one set of warning light lenses than one for every market/model/options.