HP C2858A Service Manual page 141

Test
Primer
Pen Continuity
X-axis encoder
Y-axis encoder
Bail Sensor
Media Sensor
Troubleshooting
8-16
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Table 8-3. Service Tests (Continued)
Description
Verifies the ability of the primer to select
individual pens and run the pump for testing
priming capability. Also tests the optical
sensor's ability to initialize the primer cam.
Checks for proper interconnection between all
four pens and the carriage. Uses a matrix of
primitives (PS) and addresses (Addr Sel) to
select nozzles to fire and determine pen ID. If
PS=00 and Addr Sel=0000, connections are
good. Any other numbers indicate a poor
contact. Press DOWN ARROW to see results
for each pen. Pens may be removed or
reseated while test is in progress. STOP the
test by pressing the ENTER button.
Verifies the operation of the servo loop
(X-axis feedback). STOP the test by pressing
the DOWN ARROW.
Moves the pen carriage assembly close to the
center of its travel and then moves the
carriage left-to-right and right-to-left. A
"POSITION=" readout at the front panel
indicates carriage position to the user.
Verifies operation of the optical bail sensor.
After the test is selected, manually raise and
lower the bail (the window sensor is disabled
during this test) and verify the display
changes in accordance to the bail position.
STOP the test by pressing the DOWN
ARROW button.
Verifies operation of the optical media sensor.
After the test is selected, manually insert a
sheet of media so that it covers the media
sensor. The display should change as the
media is inserted and removed. STOP the test
by pressing the DOWN ARROW button.
Assemblies
Tested
Pens
Primer Assembly
Optical Sensor
Pens
X-axis Encoder
X-axis Encoder
Cable
Main PCA
Y-axis Encoder
Y-axis Encoder
Cable
Main PCA
Encoder Strip
Drop Sensor
Drop Sense
Cable
Bail Sensor Flag
Main PCA
Mechanical
Interference
Media Sensor
Main PCA
Reflector Label
Media Opacity