On the way to emission test check engine light came on. I thought it would not pass but,it did.They did not use the OBT because the truck was over the weight limit. they used the exhaust to test. Got two codes,1260 theft detected .this I think was the remote start is not working.I bought this used so I have no idea what system they put in.the other code is 2270 ox sensor stuck lean,bank 1.Iam not shure but the temp in MD got down to 34 degrees.Where is this sensor and how hard is to replace. how can I clear these codes?