My 2005 S40 turns on the check engine light, the codes P0031, P0037 sensor 1 and 2 are readed. I change the sensors in town the dealer recommends bosch or original one. Then I realize that the car uses bosch ones the I decide to use the same. But the lights remains on. I check for bad contact, wires, etc and everything is ok.

Any ideas what could happen?

 

are you saying you cleared the codes and they returned or did you not redo the OBD2 scan and clear the codes after installing the new parts?

 

Yes,
I clear the codes. I was expecting to do not turn on after a 40-60 miles... but

 

Check fuse F33. Those codes are for failures in the heater circuit for the sensors, and they both share the same fuse to power that circuit.

 

Ok, I will check that today. I let you know guys. Thanks!