No dtc codes being held in the computer so it will not pass smog check

I have a 91 s-10 4.3l v6, also. hook up the code reader hit the erase button then do an oil change air filter change and run a can of "smog check pass" available at any auto parts store. you should pass smog then.

DO YOU MEAN MONITORS? NO CODES IS GOOD

No codes is a good thing. If you mean they can't interface with it that a whole different story. Check fuses first. But need to see the data, maybe something is wrong just enough to keep monitors from setting.