Perhaps the info here might be of help to you...Fuser Related Status Codes & how to reset them:
C123 style (C123/128/133, M123/128/133, Pro123/128/133) 010-313
Fuser Control Thermistor failure (open Control Thermistor) 010-314 Fuser Side Thermistor failure (open Side Thermistor) 010-318 Fuser temperature did not rise quickly enough during heating cycle 010-320nakeder Overheat (must be reset from diagnostics by resetting NVM (Non Volatile Memory code 744-220 back to "0") * 010-327* Fuser took too long to warm up (must be reset from diagnostics by resetting NVM (Non Volatile Memory code 744-220 back to "0") * * C123 style: Resetting Fuser Codes (010-320, & 010-327) Accomplished by resetting NVM code 744-220 to '0'... First enter UI (User Interface) Diagnostic Mode: Hold down the '0' button for 5 seconds and then press the 'Start' button while still holding the '0' button. The machine will prompt you for a Password. Enter the default Access Number: '6789' and press "Confirm". The colors on the display will be reversed to indicate that you're now in diagnostic mode. Next press the Dual Heat Lamp Assembly (C123 version) www.partsdrop.com
201-387-7776 Page 4 of 5 AC Connector: C123 version "Log In/Out" button on the Control Panel. Select 'System Settings', 'Common' Settings, followed by 'Maintenance / Diagnostics'. Now you will find the main menu includes one choice called "NVM Read / Write" (NVM is Non Volatile Memory)... Now you can enter your "Chain-Link" code (in this case 744-220) and press 'Confirm / Change'. The current value will appear (if the machine is in a fuser fault condition, the value will be set to "1"). Select the "New Value" column and input your new value ('0'). Select "Save" and the new number should now appear in the "Current Value" column. You can turn the power off and back on at this point. The machine will attempt to warm up the fuser again. If the condition which caused the fault in the first place is still happening, the Status Code will return after a few minutes of attempting to warm up. C118 style (C118, M118, M118i) U4-1000 (U4-1) Fuser failure (did not come up to temperature in time)... must be reset from diagnostics (NVM code 50-20 must be reset to '0')*. U4-2000 (U4-2) Fuser over temperature.... Must be reset from diagnostics (NVM code 50-19 must be reset to '0')*. U4-3000 (U4-3) Fuser thermistor circuit is detected as being an open circuit. * C118 style: Resetting Fuser Codes (U4-1 or U4-2): Enter diagnostics (from the powered on state, hold down the '0' button and then press 'Start'. The display will change to opposite colors to show you it's in diagnostics)... Select 'Chain-Func' in the 'CE Setting' screen by using the 'Select' button, followed by 'Enter'. Select "NVRAM R/W". Enter the "Chain" (in this case '50'). Next select "Func" (function) by using the "Select" button. Enter the "function" ('20' if you're clearing a U4-1 code or '19' for clearing a U4-2 code) followed by 'Start'. The current value for that memory code (50-20 or 50-19 in these cases) will appear in the "Read" column (if the machine is in a U4-1 or U4-2 status condition, the value will read as '1'). Change the value by pressing the "Select" button at the "Read" column to switch to "Write". Enter a '0' for the new value, and then press 'Start'. Finally, select "Write NVM". You'll probably be well served by being able to test the lamp and thermistor circuits from the AC Connector so you know what you're looking to replace before you even rip into the fuser. On the C123 & WC-5225 versions, there are slots for 8 pins (2 rows of 4 arranged vertically). Pin 7 is on the upper left and Pin 8 on the upper right is empty. Pins 7 & 1 are one of the two Heat Lamp Circuits. Each Heat Lamp Circuit goes through its respective half of the Heat Lamp Assembly, and then through both thermal fuses to the return wire (pin 7 is the return wire which is common to both heat lamp circuits). Pins 7 & 3 are the other Heat Lamp Circuit. If either Thermal Fuse is blown, neither lamp circuit will conduct. If one circuit measures good and the other measures bad, then the Heat Lamp Assembly must have failed. The Thermistor circuits for the C123 are between Pins 2 & 4 and Pins 5 & 6. If you set your meter to 200K ohms, you can measure the Thermistors... they should measure a high resistance and then if you were to warm up the Thermistor's head, the resistance should begin to drop. These Thermistors are unusual in that the heads are ***** (no yellow kapton tape). www.partsdrop.com
201-387-7776 Page 5 of 5 AC Connector: C118 version The C118 fuser's AC Connector is shaped the same as the C123 version (slots for 8 pins) however there are only 4 pins actually present and they numbered the pins differently for this one. On this one, Pin 2 is in the upper left corner and Pin 1 is in the upper right. On this connector, Pins 1 & 3 form the Heat Lamp Circuit. The Thermistor Circuit is between Pins 2 & 6. Hope this turns out to be valuable information for you. It'd be a shame to replace one of these fusers and then throw out or return the used one without at least inspecting it for the possibility of fixing it for the next customer who needs one. Be a green-tech and fix'em when you can. Happy Repairs everyone! Britt works for The Parts Drop, a company whose primary business is providing parts, supplies and information for Xerox brand copiers, printers and fax machines. You can find more information, including many of Britt's past ENX articles on their website, www.partsdrop.com.
If you'd like to read more about Xerox brand office equipment, there's also a complete listing of past articles under contributing writers on the ENX website (www.ENXMAG.com).
Hope this was helpful, good luck!