Service manual

Troubleshooting
5-5
Power-ON diagnostics failures are reported in the upper-left corner window of the system startup
screen. Refer to System Startup on page 5-9 for more information.
Extended Diagnostics
Extended diagnostic tests can be manually initiated only during system startup. The kinds of tests
and features available in the extended diagnostics are:
•Power-ON tests.
• Interactive tests and read/write memory tests that are not appropriate during power-ON
diagnostics.
• Touchscreen calibration and data dump utilities.
• System data dump and system reset utilities.
The diagnostics menus allow most of these tests to be run individually or all at once. If Loop mode is
activated, a test(s) can be executed in a continuous loop. If Halt On Error mode is activated, then the
looping stops when a diagnostic failure is detected. To avoid false failures, do not use the
touchscreen, mouse, or keyboard while the diagnostics are executing.
For detailed information on the extended diagnostics and how to run them, refer to System Startup
on page 5-9, Boot Menu on page 5-10, and Diagnostic Menus on page 5-12.
Diagnostic LED
If during the boot process the CPU determines that it cannot continue to boot, the CPU will stop
booting and repeatedly flash an error code on a diagnostic LED. The diagnostic LED is located in the
center of the CPU board and is visible by looking through the ventilation holes above the SDLC
connector on the back of the unit.
During the boot process, the LED normally flashes on about once every four seconds to indicate that
it is working. If the CPU cannot boot, the LED flashes an hexidecimal error code with the most
significant character first. Leading zeros are not displayed. Each character is represented by a
series of short flashes that count up to the character value (for example, two flashes = 2 hex, fifteen
flashes = F hex, etc.). A zero character is indicated by a long flash. Each character is separated by a
short pause. After the error code is completed, the LED pauses for about four seconds before
repeating the error code. Error codes and their meanings are described in the following section.
Monitor Fails Power-ON Diagnostics
Troubleshooting Method 1: Using the Touchscreen
1. Display the Diagnostic menu.
The Diagnostic menu is activated using the mouse. Left-click followed by a right-click
during the “3-2-1” countdown.
2. Click the test parameter key that retests the previously-indicated failure.
Upon verification of the failure, a message provided by the monitor directs you to the field
replaceable unit that failed.