2000 Chevy S-10 looking for help on smog pump

hi, I am replying to the response about the air pump on my truck.Some one replied and said the airpump probably doesnt work anymore and that there ia a tsb for installing a shield to protect from water.What does tsb mean and also the person replied that they will update this any help would be great.and how difficult is it to replace and possibly how much?The light has gone off before to pass inspection then came back on but it has been 2 years since it sounds like that may be the problem.could I just dissconnect plug then plug back in to see if the service engine light will go off or do I have to wait until the computer resets itself? thanks for the time and help.

Ken Hellman