HP M750 series

Problem Sample Cause Solution
Some color is misregistered.
The product is incorrectly
calibrated.
Calibrate the product.
The ITB unit is defective. If the ITB does not rotate smoothly or
a cleaning malfunction occurs (ITB is
dirty), replace the ITB.
The drive gear of the ITB motor
is worn or chipped.
Check each drive gear between the ITB
drive roller and the ITB motor. If the
gear is worn or chipped, replace the
drive unit.
The RD sensor is defective. Open and close the right door several
times to clean the RD sensor. If the
problem persists, replace the RD
sensor.
The laser/scanner unit is
defective.
Replace the laser/scanner assembly.
The print cartridge is defective. Replace the print cartridge of the
affected color.
Toner smears appear on the
media.
The product has residual media. Remove the residual media.
Poor contact exists in the
primary charging bias or
developing bias contacts
between the print cartridge and
the product.
Clean each contact of the color that
produces the missing color. If the
problem remains after cleaning, check
the contacts for damage. Replace any
deformed or damaged parts.
The fuser inlet guide is dirty. Clean the fuser inlet guide.
The printed page contains
misformed characters.
The product is experiencing
page skew.
See the “Text or graphics are skewed
on the printed page” row in this table.
The laser/scanner unit is
defective.
Replace the laser/scanner assembly.
Text or graphics are skewed on the
printed page.
The registration shutter spring
is unhooked.
Check the spring and place it in the
correct position.
The registration shutter spring
is deformed.
Replace the cassette pickup assembly.
The printed page contains
wrinkles or creases.
The roller or media feed guide is
dirty.
Clean any dirty components.
A feed roller is deformed or has
deteriorated.
Replace any deformed or deteriorated
rollers.
The paper feed guide is
damaged.
Replace the paper-feed-guide unit.
ENWW Solve image-quality problems 521