10 Turn the printer off and unplug the power cord.

Replace the transfer charger unit.

Power-on-reset the printer.

Run test prints.

Has the problem been resolved?

No: Replace the upper paper guide assembly. If this resolves the problem, turn to TAG 002: Check & Problem Resolution. If this does not resolve the problem, replace the high volt- age unit, then turn to TAG 002: Check & Problem Resolution.

Yes: The transfer charger unit was at fault. Turn to TAG 002: Check & Problem Resolution.

11 Open the front cover and install an interlock by-pass tool.

Remove the photoconductor unit.

Remove the developer unit.

Run diagnostic test 010.

Watch the toner motor coupling in the developer unit cavity.

Does the coupling turn?

No: Go to #20 in this TAG.

Yes: Continue.

12 Inspect the toner drive coupling on the developer unit for damage.

Is the coupling damaged?

No: Continue.

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

13 Rotate both the drive couplings on the developer unit clockwise.

Do both drive couplings rotate freely?

No: Replace the developer unit, then turn to TAG 002: Check & Problem Resolution.

Yes: Continue.

14 Reinstall the photoconductor unit.

Run diagnostic test 009.

Watch the developer drive coupling in the developer cavity.

Does the coupling turn?

No: Repair or replace the main drive gear assembly, then turn to TAG 002: Check & Problem Resolution.

Yes: Continue.

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Troubleshooting Analysis Guide (TAGs)

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Image 206
HP C30 manual Does the coupling turn?, Do both drive couplings rotate freely?