Oki ML421 Maintenance Manual - Page 97

42113901 (3) Fatal Alarm Rev.2 Table 6.3 (1/2) ALARM CATEGORY ALARM MAIN CONTROL ALARM MPU internal RAM alarm Program ROM alarm RAM on Control Board alarm EEPROM alarm ALARM 10 WDT (Watch Dog Timeout) alarm FIRMWARE DETECTION NMI signal alarm ALARM BRK instruction alarm MPU internal RAM alarm SERIAL ROM alarm INTERFACE ALARM RAM on I/F board alarm I/F not mounted LED DISPLAY 12 15 17 20 PROP HSD UTL NLQ REMARKS Read/write error TROUBLESHOOTING Replace Control Board Check sum error Read/write error Replace ROM or Control Board Replace Control Board No reaction when MPU reads data MPU is locked up and it ios reset after 65ms. NMI port of MPU is kept low level. FFFF data is detected due to MPU locked up. Read/write error Check sum error Read/write error No reaction from serial I/F board Replace Control Board Turn the power OFF and ON or replace Control Board Turn the power OFF and ON or replace Control Board Replace ROM or Control Board Replace RS232C I/F Board Replace RS232C I/F Board Replace RS232C I/F Board Replace RS232C I/F Board or Control Board. : LED Blink (200ms ON, 200ms OFF) : LED Lights up Oki Data CONFIDENTIAL 97 /