HP 8550mfp Service Manual - Page 379

Table 41. Numbered printer messages (continued) 54.1 TEMPERATURE SENSOR ERROR CYCLE POWER Event log message: 54.00.01 Description: Indicates that the temperature/humidity sensor in the printer has malfunctioned. The temperature/ humidity sensor is located below tray 2. Action: 1 Reconnect connector J801 and relay connector J55 on the temperature/humidity sensor, and connector J206 on the controller board. 2 Replace the cassette crossmember assembly which includes the temperature/humidity sensor. 3 Replace the controller board. 54.2 CAROUSEL ERROR CYCLE POWER Event log message: 54.00.02 Description: Indicates that the color toner carousel is not working correctly. This could be caused by an obstruction in the carousel path, such as a loose shutter or disengaged toner cartridge. Action: 1 Turn the printer off and on to reset the printer. 2 Open the carousel door and waste toner tray. Look for an obstruction, such as a toner cartridge shutter catching on the waste toner tray. Verify the toner lock lever is fully locked. If the message does not clear after closing the doors, turn the printer off and on to reset the printer. 3 Clean the carousel position sensor (PS3) with compressed air. If the problem persists, replace the sensor. 4 Reconnect connector J701 on carousel motor PCA; connectors J641, J642, J644, and J648 on the main relay PCA; connector J672 on the subrelay PCA; and connector J102 on the power supply. 5 Check operation of the carousel stopper arm. Replace the carousel stopper solenoid. 6 Check electrical continuity between connector J641-1 (+24 VB) and J642-3 (PMP) on the main relay PCA when the door switch (SW641) is turned on. If there is no electrical continuity, replace the main relay PCA. 7 Check electrical continuity between connector J644-1 (PBK) and J644-2 (PMP) on the main relay PCA when the door switch (SW644) is turned on. If there is no electrical continuity, replace the black toner cartridge on/off switch. EN Printer message troubleshooting 377