Hi I've got a 2006 with the 2.4L
I had no engine lights but a slight exhaust leak. Changed the flex pipe/downpipe now I have these codes. When I clear them P0141 comes up within a few seconds and P1157 comes not too long after. I thought maybe i pulled a wire our of a connector or something but I've double checked all the connectors and wires to the connectors and they look fine.
I did beat the bolts/studs out of the flange on the cat with a hammer with the sensor installed. I did use a torch to heat up the upstream sensor when removing it but nothing crazy its just a little propane torch. So I've considered maybe this abuse caused the downstream sensor to fail, and the heat on the upstream sensor since these codes are for both sensors but damn what are the odds I messed up both?
I've checked all the fuses with a test light and swapped out the LAF relay with another and no luck.

 

You mentioned you checked fuses. For the P1157 A/F fuse #4 15A and fuse #23 IGP 7.5 amp. Both are in the under dash fuse box.

You may want to check the wiring on the engine wire harness with a test light or volt meter to see if there is an issue with the wiring.