Copy processor board LEDs The CPB has four light-emitting diodes (LEDs) (callout 1) located at the back of the MFP. These LEDs illuminate in specific patterns depending on the status of the CPB. The table in this section details what occurs at each stage of CPB initialization. Hint The LEDs can be difficult to see through the holes in the CPB faceplate in a high-light environment. It may be necessary to turn off some lights or remove the faceplate to properly troubleshoot the LEDs. The LED patterns displayed by the HP LaserJet 9000mfp are opposite those displayed by the HP LaserJet 4100/4101mfp because the CPBs are mounted differently. 1 Figure 61. Copy processor board LEDs Table 20.
Copy processor board LEDs 96 Chapter 5 Theory of operation C8523-90921 LED pattern CPB status First stage of CPB initialization 1 1 1* 1* Memory DIMM detected Firmware DIMM detected * LEDs might flash MIPS processor functional before final continuous MIPS processor communicates with the ASIC illumination Note If the LEDs stay in the illuminated state, a CPB failure has occurred (for example, a memory DIMM is not present or fully seated). 1 1 0 1 The MIPS processor is communicating with the PCI Bridge 0 1 0 1 The MIPS processor is communicating with the FPGA 0 0 0 1 A check of the FPGA’s SRAM is performed