Xerox Phaser 6180, Service Manual, Page: 237 / 616

Phaser 6180 Color Laser Printer Service Manual 4-3
General Troubleshooting
Power On Seflf Test (POST)
POST Diagnostics provide a quick mean of isolating a defective subsystem
associated with the Image Processor Board and SDRAM. POST returns
control to the boot loader and the operating system is loaded.
The following tests are performed when the printer is powered On.
1. Checks and initializes CRU Register.
2. Initializes ASIC.
3. Checks RAM.
4. Initializes the Control Panel driver.
5. Processes the ROM Sum Check.
6. Initializes Memory Manager.
7. Initializes EEPROM driver.
8. Initializes IOT Controller.
9. Starts the Operating System process.
10. Printer is Ready.
POST Test Description
Test Chain Link Description
CodeROM 116-317 This test calculates the ROM checksum chip by
chip and compares it with the value stored in the
CodeROM itself.
Checksum error is in the main program ROM.
FontROM This test calculates the FontROM checksum chip
by chip and compares it with the value stored in
the FontROM itself.
116-310 Checksum error is in the built-in FontROM.
116-317 Checksum error is in the main program ROM.
EEPROM This test writes/reads/verifies on the diagnostic
area of the EEPROM.
116-323 Error is detected in EEPROM0 during
initialization.
116-326 Error is detected in EEPROM1 during
initialization.
DRAM This test checks OPEN/SHORT of the address
line of the DRAM. This test also writes/reads/
verifies on the entire DRAM.
116-315 Error is detected if included RAM is different.
116-316 Error is detected if extended RAM is different.
116-320 Error is detected if extended RAM is not
supported.