When was the last time the developer was replaced in the developer unit? If has been replaced then you might have a bad ATDC (Automatic Toner Density Control) sensor Located at the rear of the drum and below. (Remove drum to see, has a white cover on it attached to a control board, needs cleaning,2nd replace. If the developer was replaced when it was done was a vacuum cleaner used? IF so the static electricity from the vacuum clear destroyed the sensor, NEVER USE a VACUUM cleaner to remove the developer. Also when the developer was replaced, was counter cleared to tell the copier developer was replaced, the copier use the counters to determine certain voltages for certain assemblies, if not image problems and codes can appear. Finally was the F8 run after the developer was installed before any prints or copies made? If not buy new developer and start over, counter is to be cleared first, then developer replaced, then F8 run.
Btw, I’m available to help over the phone in case u need at
https://www.6ya.com/expert/normanj_7893313f0751935f
×