Xerox 7700DX Service Manual - Page 63

POST Faults, Fault Reporting Devices, LED Blink Patterns, and pressing OK. - code

Page 63 highlights

POST Faults There are two kinds of faults: Soft and Hard. A soft fault is any fault that is discovered by POST but does not prevent the operating system from initializing and becoming available as a tool for troubleshooting. These POST faults do not stop execution and are reported on the StartPage, in a red box, after the system is running. A hard fault is any fault discovered by POST that prevents the operating system from initializing successfully. A hard fault prevents the system from further execution and is halted with blinking LEDs (front panel and health LED). The test name of the test that failed is displayed on the front panel. Note With the DIP switches in service mode, a soft fault is converted to a hard fault. Fault Reporting Devices There are four fault presentation devices. For hard faults: ■ The health LED flashes according to the fault code. ■ The front panel LED flashes in unison with the health LED. ■ The last posted message to the graphic front panel is present. ■ All soft faults are printed on the StartPage (when the DIP switches are in Customer Mode), see You can print a service Diagnostics menu map by highlighting "Print Service Menu Map", using the arrow key and pressing OK. on page 2-35. LED Blink Patterns For faults identified as hard faults, the POST firmware causes the PS health LED to blink in a particular pattern to identify the fault. There are short and long blinks. A long blink is worth 5 and a short blink is worth 1. If a fault blink pattern is flashed as long, long, short, short, this is fault code 5+5+1+1=12. The exception to the above pattern is a RAM test error. The RAM tests have a special blink pattern and the front panel displays "RAM Error." During power up the front panel LED is On. If the RAM tests fail, the Image Processor Board health LED is turned Off, and the front panel LED is red. At 1/2-second intervals, the health LED and the front panel LED toggle continuously. Phaser 7700 Color Laser Printer Service Manual 2-33

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Phaser 7700 Color Laser Printer Service Manual
2-33
POST Faults
There are two kinds of faults: Soft and Hard.
A soft fault is any fault that is discovered by POST but does not prevent the
operating system from initializing and becoming available as a tool for
troubleshooting. These POST faults do not stop execution and are reported
on the StartPage, in a red box, after the system is running.
A hard fault is any fault discovered by POST that prevents the operating
system from initializing successfully. A hard fault prevents the system from
further execution and is halted with blinking LEDs (front panel and health
LED). The test name of the test that failed is displayed on the front panel.
Note
With the DIP switches in service mode, a soft fault is
converted to a hard fault.
Fault Reporting Devices
There are four fault presentation devices.
For hard faults:
The health LED flashes according to the fault code.
The front panel LED flashes in unison with the health LED.
The last posted message to the graphic front panel is present.
All soft faults are printed on the StartPage (when the DIP switches are
in Customer Mode), see You can print a service Diagnostics menu
map by highlighting “Print Service Menu Map”, using the arrow key
and pressing OK. on page 2-35.
LED Blink Patterns
For faults identified as hard faults, the POST firmware causes the PS health
LED to blink in a particular pattern to identify the fault. There are short and
long blinks. A long blink is worth 5 and a short blink is worth 1. If a fault blink
pattern is flashed as long, long, short, short, this is fault code 5+5+1+1=12.
The exception to the above pattern is a RAM test error. The RAM tests have a
special blink pattern and the front panel displays “RAM Error.”
During power up the front panel LED is On. If the RAM tests fail, the Image
Processor Board health LED is turned Off, and the front panel LED is red. At
1/2-second intervals, the health LED and the front panel LED toggle
continuously.