System Error Codes System Error Codes A System Error Code appears on the Front Panel when an unrecoverable system exception interrupt occurs in the Printer. nnnn: System Error Code The System Error Codes are listed in the following table: Corrective Action 1. Replace the Main PCA ⇒ Page 8-35 . 2. Upgrade the Printer Firmware. 2-18 HP Designjet 9000s Series Printer Service Manual System Error Code Error Description F es: 0001 _ Operation Code Exception F es: 0002 _ Slot Illegal Exception F es: 0003 _ Address Exception F es: 0004 _ DMA Error F es: 0005 _ NMI Occurrence (WatchDog Error)