Here is the deal with my MX360 4 in 1 printer, no one mentioned that the encoder film has to go into a sensor on the back side of the ink cartridge carrier, which is hidden from view, on my printer which started out with a 5100 error, continued to exhibit this error because the film was no longer INSIDE the sensor, it was riding the backside of it causing the 5100 error to continue. I only found this out after I angerly destroyed the whole printer over riping a ribbon wire that went to the ink carriage trying to figure out why the error never went away. I also took it apart because one of the hoses from the ink absorber had come off and was rapped up inside the pump! Then one of the hoses never reached the same area as the other with no clue as to why one hose was way shorter than the other hose not reaching its intended area as the other one was situated. See my image below showing the sensor with the encoder film where it should be, you are looking at the back side of the board that is behind your ink cartridges. This sensor faces the back side of your printer. Make sure that film is inside that sensor slot!!! It is very difficult to see where it goes without taking the carriage out of the printer rail entirely! That film in my photo is the one you are told to wipe with a clean rag. I wasted a good printer over the lack of this information being available on line or in service manuals! It's too late now for my MX360, its trashed, but hopefully I can save other people the heartache! Make sure you focus on that area if cleaning that strip does not clear that 5100 error, it may not be just a paper jam or paper obstruction.
Bruce.
