My S80 '00 T6 (140k miles) shows CEL all the time. When it happened 2 years ago, the dealer told me there was nothing wrong. So I did not bother. Still it shows up.

So today I tried OBD scan and got PO237 and PO236 readings, which point to turbo boost pressure sensor. The car runs fine.

However, being in California, I am sure that I will have problems with trying to pass the smog test. I tried to reset with the scanner but the CEL came right back. Should I replace the sensor? Where is it located anyway? Thanks for help.