Q: 2007 Ford Fusion Airbag Code B2290

It has airbag warning light turns on & passenger air bag light goes off, after few seconds of ignition/engine on. I hooked up the scanner and it gives B2290 code stating Occupant Classification System fault, I tried erasing the code, but unable to do it, as it comes right back on. I unplugged the wiring to OCM (or occupant detection / weight) sensor part#14B422 underneath the passenger seat, and then ofcourse U1900 came which says SRS module fault, but then I was able to erase the B2290 code, and not U1900. I also took it to a body shop as they have high end diagnostic tools, and they said recalibrating the OCM sensor should fix the issue, they tried to recalibrate it two times was successfully completed but the code didn't go away. So they are suspecting that OCM sensor could be bad itself, and need to be replaced. Its an expensive part $180, I don't want to just replace it, if its really not required. Looking for 2nd opinion or suggestion to how to really identify the problem part.

My car has 90000 miles.
My car has an automatic transmission.