Troubleshooting Analysis Guide (TAGs) 3-47
TAG 031: Toner Patch Reference Level Too Low
Error Code: 031
Possible Causes: Contamination of the toner patch sensor or printhead lens
Possible Defects: Photoconductor unit
Connectors or wiring
PCL board
Developer unit
1
Turn the printer off and unplug the power cord.
• Perform the every-call cleaning procedure, described in Chapter 9, “General Printer Mainte-
nance”.
• Clean the toner patch sensor on the developer unit.
• Clean the printhead lens.
• Run at least 200 test prints to detone the printer’s engine.
Has the problem been resolved?
No: Contamination was at fault. Turn to TAG 002: Check & Problem Resolution.
Yes: Continue.
2
Check the voltages, as described in Chapter 9, “General Printer Maintenance”.
Are the voltages correct?
No: Replace the high voltage power supply unit, then turn to TAG 002: Check & Problem
Resolution.
Yes: Continue.
3
Have the photoconductor and developer units been replaced recently?
No: Continue.
Yes: Go to #6 in this TAG.
4
Replace the photoconductor unit.
• Run 200+ test prints to reduce toner concentration in the developer unit.
Has the problem been resolved?
No: Reinstall the original photoconductor unit and continue.
Yes: The photoconductor was at fault; turn to TAG 002: Check & Problem Resolution.
5
Replace the developer unit.
• Run test prints.
Has the problem been resolved?
No: Reinstall the original developer unit and continue.
Yes: Turn to TAG 002: Check & Problem Resolution. If the problem reappears, the toner/car-
rier mix may be old or contaminated.
