Toner is new , seal pulled , toner access on toner unit and developer unit seem to open fine . Cleaned machine up a bit , very dusty . Drum looks in good shape . Stopped mid copy , little to no image on drum . Not getting a low toner error , is there one ? Toner counter says 78% remains . I have the service and parts manuals . Looked at diagnostics , found test mode 111-0070 to test toner sensor black , it changed as it ran from about 73 to 120 , not sure what is normal for this . Looked at the counters for Field replaced items , not clear at all , said the dev unit was at 3417 life count , but the machine has not been serviced in over a year , has 350,734 pages on it . Pulled the HVPS and cleaned it up and examined it and gave it the sniff test , looked good , no burnt areas and no burnt smells . I did not remove and inspect the drive between the toner and developer unit , ran out of time . Thanks in advance , Ark .