General Troubleshooting 4-3Power On Self Test (POST)POST diagnostics provide a quick means of isolating a defective subsystemassociated with the Image Processor Board and SDRAM. There are two kinds ofPOST faults: soft and hard. A soft fault is any fault that allows the operating system toinitialize. Soft faults do not stop printer operation and are reported on the Startup pageafter the system is running. A hard fault prevents the operating system frominitializing stopping further printer operation. Hard faults are indicated with blinkingLEDs and the failed test appearing on the display.The following tests execute when the printer is powered on after the Boot Loaderruns, and before the operating system is loaded and initialized. Bypass POST bypressing the OK button at power on until the splash screen displays.POST Test DescriptionsTestFaultCodeFaultType DescriptionSDRAM 1 Hard This test fails if the boot loader finds no or faulty RAM (Runprior to POST). The boot loader displays “RAM ERROR” andblinks the Health and Control Panel LEDs.Control Panel Hard This test checks the Control Panel connection and firmware.A fault is indicated on the Health LED.EEPROM 10 Hard This test checks addressing of the EEPROM.Ethernet 11 Soft This test checks the ethernet core.CPUInterrupts12 Hard This test checks that each interrupt to the CPU is functioning.USB 13 Soft This test checks that the USB core is functioning properly.Real-TimeClock14 Soft The real-time clock is tested.Min. RAM 16 Hard Checks that there is at least 128 Mbytes installed. ControlPanel displays “Install More RAM” on failure.Max. RAM 17 Soft Checks that there is no more than 1 GB installed.IDE Disk 20 Soft Checks for a hard drive, then checks the disk controller core.
