Lexmark 4049LMO Service Manual - Page 40

4049-XXX J9-1 and between +15 and +20VDC on engine board J9-2. Shorting engine board J9-2 to ground should turn on all the erase lamps. Check the erase lamp cable continuity. Replace the transfer roll housing if the voltage and the cable are good. Inspect the contacts on the HVPS; make sure each spring-loaded contact returns when pressed and released. Rough Paper mode can cause background on some papers; if Rough Paper mode is on, turn it off and run the print test again. Printing on coated paper or using refilled print cartridges can also cause background. Run the Print Test with the RIP Board removed and check the following voltages; then stop the test and check the voltages again: Connector J13-1 J13-2 J13-3 J13-8 Voltage while Printing Less than 5 VDC Less than 5 VDC (Fluctuates between pages) +1.5 VDC Less than 1 VDC Voltage while Idling 0 VDC 0 VDC 0 VDC +6 VDC If any voltages are not correct replace the engine board. If no problem is found, enter the diagnostics mode and change the Charge Roll setting. Users who run large jobs with very dense graphics in high humidity environments may get some print quality improvement from increasing the Transfer setting; users with more normal jobs will see no difference. Make sure the HVPS contacts to the transfer roll housing are in good condition. Black Page Black output is usually caused by an incorrect high voltage in the printing process, resulting in toner development on the entire photo- 2-13