I had a faint line of missing toner on the print, so I ran diagnosis and it said it was magenta imaging unit problem. (First photo) Replaced that, and the pages started coming out with a spray of pink from the bottom edge to the middle. (Second photo) Figured it was bad imaging unit; went to replace it. it wouldn't come out. It was off track inside the machine. So I called technician. He removed Accumulator Belt Assembly tray and got the imaging unit out. Put in a new one, and now I don't get any colors except magenta, and only in about 1/3 of the page from the bottom to the middle. Very solid coverage until it disappears. (Third photo) .He had a very difficult time getting the Accumulator Belt Assembly back in the machine, and I'm wondering if he knocked a sensor loose. Tech is saying machine is unrepairable; I find that hard to accept as the problem got worse after the repair.
Sounds like the magenta drum rail was bent. If it was forced it may have caused additional damage to the latching system. Take all the drums out and compare each drum rail to see if the magenta rail looks bent. Look at the left and right side of the black drum handle and see if the timing arrow lines up properly.