HP 250C - Manual (Page 165)

8Ć31 Troubleshooting C4699Ć90000
Carriage cannot park
in service station.
Mispositioned trailing cable: The trailing cable may be
preventing the carriage from reaching the leftĆhand stop. Make
sure that the trailing cable is positioned under the plastictabs at
the back of the carriage cover, and not above them.
Drive belts wear out
prematurely.
Diazo copiers: The belt may wear prematurely if the plotter is
placed near a diazo copier that uses ammonia to produce blueĆline
copies. The material used in the belt is very reactive to ammonia
vapor. The vapor is very corrosive and can damage other parts as
well. Move the plotters away from such copiers.
Storing: Keep new belts in their bags with dissicant until you need
to install them. This is to avoid incorrect swelling.
Noisy carriage
movement.
Dirty carriage wheel: Remove aluminum or dust particles from
the wheel at the back of the carriage, and from the slider path along
which the wheel moves.
Bail mechanism fails. Wearing of parts: The cam gear and engaging gear may not make
correct contact with the left driveĆroller gear even though the
carriage is actuating the engaging lever. This can happen due to
excessive wearing of parts. Another problem may be that the bail
cable has broken.
Carriage motor control: The carriage may not properly locate
the engagement lever, preventing the gears from engaging. Any
problems with the carriageĆmotor control system (for example, the
encoder strip) or associated mechanics could cause this problem.
Also, if the carriage cannot find the true left stop during
initialization (caused by interference), the engaging lever cannot be
located.
Bail cam: The bail may fall from the up position. This can happen
if the cam is over or underĆrotated. The notch on the cam, used to
engage the left bail bracket, is not properly located for the bail up"
condition, and the bail falls abruptly. Perform a bail cycle test.
Adjust carriage: If the carriage moves over the engaging lever
without raising it, you may need to adjust the carriage angle on the
slider rod. (Details ' page 7Ć11.) However, be careful not to
jeopardize the print quality, which is very sensitive to the carriage
angle.
Bail starwheels slip
off overdrive roller
wheels. Media jam.
CĆclips: Ensure that the cĆclips and bushings are correctly installed
on the left end of the overdrive roller, to prevent its movement from
side to side.
Ink spilling. Spittoon and ink separator: You need to replace these parts
when they fill up with ink. (See ' chapter 4.)
Static charge causing
media jams.
AntiĆstatic brush: If this brush (located under the entry platen) is
damaged or removed, static charge can build up on the media. A
charge can cause the media to stick to itself and jam the plotter.