[SOLVED] / EXPLANATION:
Got this "faulty" 1050 from a friend and tested with my working disks that I use on some Ataris.
When try to load some disks on this "faulty" 1050, I got BOOT ERROR message. First thing that I noticed is that the red led of the disk status on "faulty" 1050 is on for a long time, when cover of disk drive is opened. Comparing with my 1050, the red led from the faulty one is on for a long time and on my working 1050 don't (short duration for me). So, opened the "faulty" 1050, cleaned, pressed the ICs, checked the head with multimeter, assembled the wires and nothing changed about the led. Everything was done before connect the SIO on the Atari and test...
So, I turned on the working 1050 with the cover opened and now I recognized the the led is not so bright, very very low intensity, so when compared to the "faulty" 1050 looks like the led behavior is not correct. Then, connected the "faulty" 1050 on the XL, booted and the disks are booting now! Sometimes I have ERROR 144 when using a Disk Application, but I have to replace the belt cause it is dry and do some lubrication.
Thanks for all and sorry for the confusion.