Volvo Repair: check engine light, volvo repair, s70 base

Question
I took my 1999 Volvo S70 (base model)to mechanic whom I'm told fix Volvos. He replace both O2 sensor before and after the catalytic converter. The check engine light still lit, he said to take it to the dealer and have them analyze it,then take back to him to fix it. What should i do or done in the first place?

Answer
Larry, you should have gone to the dealer or Volvo repair shop first.  WHat codes did he get?  Did he scan the car? WHy should you take it back to him to fix?  The dealer is going to charge you for the scan so might as well let them fix it.  Did he use garbage 02 sensors or Volvo?  Roger