After not being used for approx 4 years, the printed page would have relatively evenly space (1/8" to 1.5") thin horizontal lines in different colors. The transfer drum would also have the lines, but after wiping it clean, they would reappear. I tried the different maintenance procedures, but the lines arer still there. Does this sound like an imager problem? In one of the posts it was mentioned to clean the LED window. Where is that located? The printer has 7800 page count.
I tried cleaning the LED lens (it didn't appear to be dirty) but it didn't eliminate the horizontal lines. see picture....
Any other suggestions?
I would at this point say the imaging unit is the problem. You will probably need to replace it.
It was probably fine when it went into storage, but toner based devices do not sit well over time.