HP 4550 manual Background scatter

Consumables that are beyond their life.

The media does not meet HP specifications. Use media that meets HP specifications (see page 67).

The toner cartridge is defective, replace the toner cartridge.

There is excess toner inside of the printer. Clean the printer (see page 148).

The transfer roller is dirty or worn.

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￿￿

￿Banding and horizontal lines

Banding occurs when solid fill areas show streaks or bands of shade variations. This can be caused by:

￿Improper consumable storage.

If the problem persists:

Print a configuration page to check the life of the consumables.

￿Replace any consumable that is past its rated life.

Banding is more visible in some halftone patterns than others. If

￿the defect occurs only once on a letter- or A4-size sheet, try printing the pattern on a legal- or A3-size sheet.

Observe the following from the test sample:

￿• Check to see if the defect spans all color planes.

•If the defect is in all color planes, does the defect produce a straight line through all color planes, or does it move from one color plane to the next?

•If the defect moves from one color plane to the next, measure the amount it moves. This movement amount is called the “procession.” Keep in mind the print order is K-M-C-Y. Measure the procession from K to M or M to C, not K to C.

CAUTION Do not expose the imaging drum to light for more than 15 seconds. The drum is light sensitive, and exposure to light can cause permanent damage.

EN

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