1995 Chevy S-10 obd1 or obd2?

The 95 s10 is obd1.

With a OBD2 diagnostic connector...according to haynes using pins 5 and 6 will flash the ses (service engine soon light on the dash)...But I believe this is a form of cash grab from GM, I have had two GM vehicles a Pontiac and the S10, neither of which I could get any sort of code from.

Check your rad shroud, it should say somewhere if the vehicle is OBD1 or 2 compliant...not that it matters doesn't work anyway....maybe there's a fuse?