Specifications

Troubleshooting POST (Power-On Self Test)/Stage Failure/POST - 3
Stage Failure/POST
POST extinguishes the LEDs from top to bottom as each test stage
passes. (The Ready LED is considered here to be the top LED). In a
functional printer, the testing process takes about 40 seconds,
after which control passes to PostScript code in ROM and the
normal warm-up continues (see “PostScript Reporting” in this
chapter).
However, if POST detects a fault during any stage, the status panel
enters an error state and flashes the bottom two LEDs forever.
Making note of the stage from which this error array first
appears can help you choose the modules to bring on a service call.
For example, suppose failure occurs during stage two (only the
top LED had extinguished before the error array appears). This
indicates an I/O board failure, so a replacement board should
definitely accompany you on site.
POST Example