HP Color LaserJet CM4730 Service Manual - Page 548

Table 6-2 Control-panel messages (continued) Control panel message Description 50.X FUSER ERROR A fuser error has occurred. The following are specific fuser errors: 50.1: A low fuser temperature error has occurred in the main thermistor. 50.2: A fuser warmup service error has occurred. 50.3: A high fuser temperature error has occurred in the main thermistor. Recommended action 5. If the message persists with different software programs and print jobs, disconnect all of the cables to the printer that connect it to the network or computer. 6. Turn the MFP off. 7. Remove all memory DIMMs or thirdparty DIMMs from the printer. (Do not remove the firmware Compact Flash.) 8. Ensure that the formatter is securely seated. 9. Remove all EIO devices from the printer. 10. Turn the MFP on. 11. If the error no longer exists, install each DIMM and EIO device one at a time, making sure to turn the printer off and on again as you install each device. 12. Replace a DIMM or EIO device if you determine that it causes the error. 13. Remember to reconnect all of the cables that connect the printer to the network or computer. 14. Upgrade formatter and DC controller firmware, which can be found in a single .RFU file from http://www.hp.com/support/ ljcm4730mfp. 15. If the error persists, upgrade the firmware compact flash card. 16. Replace the formatter and calibrate the printer. NOTE: Formatter failures producing 49 errors are extremely rare. Formatter replacement is probably not required. 1. Turn the MFP off and allow it to cool down. 2. Reinstall the fuser, and check the connector (J5001) that connects the fuser and the printer. Replace the connector if it is damaged. 3. Replace the fuser. 528 Chapter 6 Problem solving ENWW