Lexmark 5016-001 manual Fuser Hot Service Check, Cold Approximately 150k to 250k ohms

5016-001

Fuser Hot Service Check

CAUTION: The fuser may be hot, use caution before removing or servicing.

Error Codes 923 and 924 may display for a hot fuser failure.

Error Code 924 indicates the engine board has detected an open in the thermistor circuit.

Note: Most of the wiring and electrical devices can be reached by removing the paper exit cover on the bottom of the fuser assembly.

	FRU	Action
1	Fuser:	Check the fuser assembly for signs of overheating
	• Assembly	or damage, especially the hot roll and backup roll.
		Also check for contaminants such as label glue or
	• Hot Roll	excessive toner buildup.
	• Backup Roll	• If contaminants are found, repair as necessary
	Bearings		or replace the fuser assembly.
		• If damage from overheating is found, replace
			the fuser.
2	Thermistor	Check for a shorted thermistor by measuring
	Assembly	across the connector located in the cable guide.
	Engine Board	•	If the thermistor is shorted, replace the
			thermistor.
		•	If replacing the failing thermistor does not fix the
			problem, replace the engine board.
		Check for signs of damage or contamination to the
		thermistor assembly. If no problem is found, check
		the resistance of the thermistor.
		Hot: CN18-1 to CN18-2:
		Approximately 2.0k - 2.5k ohms
		Cold: Approximately 150k to 250k ohms
		If incorrect, replace the thermistor.
		Check for an open in the thermistor circuit in the
		fuser assembly. Be sure the thermistor is properly
		connected to the thermistor cable in the bottom of
		the cable guide.

Diagnostic Information 2-57