Introduction
This chapter explains how to use the built/in Service Tests (Diagnostics) and what to do if the tests fail. If possible, always perform a Service Test on the component that you are about to replace, just to make sure that is the component that has failed. If the test on that component passes, there is no need to replace it.
Power/On
The Printers automatically perform a series of internal self tests and mechanical initialization sequences whenever the user switches the Printer on. If a failure occurs, an error is indicated on the front/panel LEDs. You can perform a failure analysis by interpreting the LED error code. (Details ' Chapter 2.)
Self Test and Normal Initialization
The power/on self test and initialization procedure does the following:
1Initializes the servo processor.
2Initializes the main processor.
3Tests communication between the main processor and the servo processor.
4Tests the EEROM checksum.
5Tests the servo/processor transfer buffer and interrupt tracking.
6Tests the ROM checksum.
7Causes the main processor to initialize certain firmware modules.
8Performs a subset of the electrical service test.
9Checks the cover sensor.
If the cover is open, nothing further happens until you close it.
10 Initializes the carriage axis (Y/axis).
11 Uses the mark encoder to check the start of the drive roller.
12 Ejects any loaded sheet.
Does not eject roll media if loaded.
13 Checks the media sensor.
14 Sets the Printer to accept media.
HP DesignJet 430, 450C and 455CA Printers | Service Tests |