10 Reinstall the developer unit.

•Run test prints.

•Check TP3-31 for a voltage change from +12 Vdc to 0Vdc while running test prints.

Does the voltage change from +12 Vdc to 0Vdc every other print cycle?

No: Go to #14 in this TAG.

Yes: Continue.

11 Turn the printer off and unplug the power cord.

•Disconnect J/P41.

•Remove the developer unit.

•Check for continuity: P4 P41-44 to P25-2, P41-47 to P25-3, and P41-50 to P25-1.

Is there continuity at each?

No: Repair or replace the connectors or wiring from: P41-44 to P25-2,

P41-47 to P25-3, or

P41-50 to P25-1;

then turn to TAG 002: Check & Problem Resolution.

Yes: Continue.

12 Verify that the connector is securely plugged into the toner patch sensor circuit board, which is mounted on the developer unit.

Is it connected properly?

No: Reconnect the connector, then turn to TAG 002: Check & Problem Resolution.

Yes: Continue.

13 Clean the printhead lens and toner patch sensor.

•Reinstall the developer unit.

•Reconnect J/P41.

•Run test prints while checking TP3-31 for a voltage change.

Does the voltage still change from +12 Vdc to 0 Vdc every other print cycle?

No: Contamination was at fault. Turn to TAG 002: Check & Problem Resolution.

Yes: Replace the developer unit and cleaner unit, then turn to TAG 002: Check & Problem Resolution.

14 Turn the printer off and unplug the power cord.

•Disconnect J/P41 and J/P24.

•Check P41-30 for continuity to ground.

Is there continuity?

No: Continue.

Yes: Repair or replace the connectors or wiring from P41-30 to P24-2, then turn to TAG 002: Check & Problem Resolution.

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Troubleshooting Analysis Guide (TAGs)