So... I did several tests with a lot of different print surfaces and no one works. Only the original one. If I put any other print surface, the IR sensor doesn't work right, and the bed crash against the nozzle (during autoleveling). Does anybody have any idea on how this IR sensor works? The print surface from partsbuilt has very low quality. I bought a new one and used it just two times and it already delaminated. A transparent film detached from the black surface with the glue. I can't believe only the original can work.