Quick Reference Service Manual
7
HP DesignJet 430, 450C and 455CA Printers
Carriage Test
Purpose Ć Verify the operation of the Carriage subsystems, like the Line Sensor and analog
multiplexer and also checks the connection between the carriage flex circuit and the cartridges.
In service mode 1, press Carriage Test (Print Quality Key).
Refer to the following list to check which LED is associated with which test. If the test passes,
the following LEDs will be lit (ON). If the test fails, the following LEDs will be flashing:
Cartridge LED Ć Black Cartridge Continuity.
Film LED Ć Magenta Cartridge Continuity.
Coated LED Ć Cyan Cartridge Continuity.
Glossy LED Ć Yellow Cartridge Continuity.
Align Media LED Ć Analog Multiplexer.
Fast LED Ć Line Sensor.
Cartridge Continuity Test Failure
If any cartridge Continuity test fails: Remove the failing Cartridge and clean the flex contacts
on the Carriage and the Cartridge. Reseat the Cartridge and try the test again. Replace the
Cartridge of the relevant failing color and perform this test again. Check and if necessary
replace the Trailing Cable. Replace the Carriage Assembly. Replace the Electronics Module.
Line Sensor Test Failure
If the Line Sensor test fails: Performing the accuracy calibration. Check and if necessary
replace the Trailing Cable. Replace the Carriage Assembly. Replace the Electronics Module.
Analog Multiplexer Test Failure
If the Analog Multiplexer test fails: Check and if necessary replace the Trailing Cable. Replace
the Carriage Assembly. Replace the Electronics Module.
Sensors Test
Purpose - Checks the operation of the cover sensor, pincharm sensor and media sensor.
In service mode 1, press Sensors Test (Media Type Key).
Activate the necessary sensor and check that the relevant LED status changes (ON/OFF). Refer
to the following list to check which LED is associated with which sensor:
Media LED Ć Media Sensor.
Sheet LED Ć Pinchwheel Sensor.
Film LED Ć Cover Sensor.
If the cover sensor fails, check that the frontĆpanel assembly is correctly connected to the electronics
module or else replace the frontĆpanel assembly. If the Pincharm sensor fails, check that the
sensor cable is correctly connected to the electronics module or else replace the pincharm
sensor. If the Media sensor fails, check that the sensor cable is correctly connected to the
electronics module or else replace the overdrive assembly (the media sensor is included as part
of the overdrive assembly). As a last resort replace the Electronics Module.
