How to SES light reset

I recently took my 2000 Monte carlo SS to chevy dealer due to SES light on. I was nofitied O2 senor needed to be replaced. So I had the replaced somewhere else due to cost. The SES light is still on how do I reset light

Normally, some sort of interface must be established, and the connected device must send a request to clear DTC and/or extinguish the MIL. There are software programs and adapters which will perform this function, as well as some stand-alone devices.

There is a possibility that you can disconnect battery power from the vehicle or pull the PCM power fuses for at least 20 minutes (sometimes longer), allowing residual power to decay, and clearing the battery-backed VRAM. If you do this, make sure you disable and Theft-Loc codes in the audio system, and do not leave the key in the ignition without having a spare in case the door locks cycle on power-up. Some will respond that way, and some will maintain the MIL even after a power-off period.

Thanks I will definitely try disconnecting the battery power first. Would a code scanner be one of the stand alone devices to clear ses light.

Some code scanners can display stored codes, turn off the MIL and clear stored codes. Others can retrieve real-time data as well, and display histories. Still other will only dispplay error codes without turning off the MIL.

I really thank you for trying to assist me with my problem, unfortunately I tried disconnecting the battery and SES light still comes on. I was told by mechanic that replaced O2 sensor I would have to drive car for a few mile to clear light. True? Any ideas where I can get software or adaptors you mentioned before.

Did the light go off at all?

I have disconnected the negative terminal wire on the battey for about 45 mins to 1 hour. I also tried going to autozone and letting them clear code ot but the ses light is still on. would removing adn replace o2 fuse do the trick. as stated before i went to chevy dealer adn they std it was o2 sensor which I have replaced both but ses light is still on. SOS...please assist my chevy friends.

Did you have them re-run the codes by any chance? Was the O2 code still there? Did they even re-connect the new O2 sensor connector?