HP LaserJet 5p/mp Service Manual - Page 65

HP LaserJet 5P Printer Service Supplement Troubleshooting Error 53 -- Memory/SIMM Errors Error 53 is indicated by a combination of the Error LED and either Tray LED, on and steady. More detail about the error is found by pressing the GO and RESET buttons simultaneously, which causes a secondary sequence of light patterns. These secondary patterns form a binary representation of the exact hardware type, device and error number in the form 53-XY-ZZ as shown in Table 4. Table 4. Memory Error Codes X-Hardware Type Y-Hardware Device 0: ROM 1: RAM 0: On board RAM/ROM 1: SIMM slot 1 2: SIMM slot 2 3: SIMM slot 3 ZZ - Error Number 00: Unsupported memory 01: Unrecognized memory 03: Unsupported memory size 04: Invalid SIMM speed 05: SIMM reporting information incorrectly 06: SIMM address conflict 07: SIMM address conflict Figure 27 explains how to read the light sequences. The initial sequence (Part 1) shows that ERROR 53 can be indicated by two different light sequences, depending on the X value: ROM (x =0) or in RAM (x =1) . Pressing GO and RESET together produces a secondary light pattern, which reveals the Y- and ZZ- values, which complete the error code (Part II) . The binary Y value is read from the top two LEDS; the binary Z value is read from the lower three LEDS. Part III of Figure 27 shows the binary values of the different light combinations. 58