Xerox Phaser 7750DXF, Service Manual

Page: 75 / 505

Error Messages and Codes 3-9
POST Diagnostic Test Descriptions
Test
Fault
Type Fault
Code Description
SDRAM Hard 1
This test fails if the boot loader finds no RAM present
or faulty RAM.
Boot loader posts the message “RAM error” to the
front panel and blinks the front panel LED and IP
Board health LED.
Local Bus/
Front Panel
Hard 2
Performed during the POST firmware initialization
phase.
If the front panel is unplugged, a hard fault is indicated
by the heath LED.
I/O ASIC Hard 3
This test determines if the I/O chip is functioning
properly.
MEM Hard 4
This test determines if the memory access function
works at selected addresses
Configuration
Chip
Hard 5
This test checks to see if the configuration chip is
present. If no chip is present the test fails and the front
panel message “Please Install configuration chip
displays.
EEPROM Hard 10
This test checks addressing of the EEPROM.
Ethernet Hard 11
This test checks the ethernet core.
CPU Interrupts Hard 12
This test checks that each interrupt source to the CPU
is functioning.
USB Hard 13
This test checks that the USB core is functioning
properly.
Real Time
Clock
Soft 14
The real time clock is tested.
RAM DIMM
Presence
Soft 15
This test examines bad or incompatible RAM DIMMs.
Min RAM Limits Soft 16
Checks that there is at least 128 MB installed and
ignores more than 512 MB.
Max RAM
Limits
Soft 17
Checks to ensure no more than 1 GB of RAM is
installed.
IDE Disk Soft 20
Checks the disk controller core, and runs a
DIAGNOSE command on the hard drive.
CPU Fan Hard 24
Checks hardware to see if a failure of the CPU cooling
fan has occurred.
Cage Fan Hard 25
Checks hardware to see if a failure of the electronics
cooling fan has occurred.