SC400 (Engine: Imaging 3: Around the Drum)

SC No.	Type	Error Name/Error Condition/Major Cause/Solution
SC490-00	D	Toner Density Sensor Error
		The sensor output value is 930 or more continuously for 5 seconds.
		Toner density sensor defective Toner motor defective Connect-Left PCB defective IOB defective
		Toner density sensor defective Reconnect the following connectors. Toner Density Sensor – Drum PCB connector Drum PCB – Drum Connection PCB connector Drum Connection PCB – Connect-Left PCB connector Connect-Left PCB – IOB connector If the connector is broken, shorted, or grounded, replace the connector. Check that the gears and rollers of the development unit are not damaged and rotate smoothly. Replace the development unit.
		Toner motor defective Check the drive gears can rotate or they are not unusually loaded. If necessary, replace the drive gear. Reconnect the following connectors. Toner Density Sensor – Drum PCB connector Drum PCB – Drum Connection PCB connector Drum Connection PCB – Connect-Left PCB connector Connect-Left PCB – IOB connector If the connector is broken, shorted, or grounded, replace the connector. Replace the drum unit.
		Connect-Left PCB defective Replace the Connect-Left PCB. IOB defective Update the engine software to the latest version. Replace the IOB.

SC No.	Type	Error Name/Error Condition/Major Cause/Solution
SC491-01	D	Drum Unit Type Mismatch Error
		Cannot communicate with the EEPROM of the drum PCB normally. An incompatible drum unit is installed.
		Connector defective or disconnected Drum PCB defective Connect-Left PCB defective IOB defective
		Connector defective or disconnected Reconnect the following connectors. Then perform a conduction inspection. If there is no conduction, replace the connector. Drum Unit – Drum Connection PCB connector Drum Connection PCB – Connect-Left PCB connector Connect-Left PCB – IOB connector Drum PCB defective Replace the drum PCB. Connect-Left PCB defective Replace the Connect-Left PCB. IOB defective Replace the IOB.

SC No.	Type	Error Name/Error Condition/Major Cause/Solution
SC491-02	D	Drum Unit Error
		No response from the device in reading/writing for 5 ms or more and this problem is repeated 5 times consecutively. The reading data of 2 locations do not match 8 times consecutively. The writing data and reading date do not match 8 times consecutively.
		Drum PCB defective Connect-Left PCB defective IOB defective
		Drum PCB defective Reconnect the following connectors. Drum PCB – Drum Connection PCB connector Drum Connection PCB – Connect-Left PCB connector Connect-Left PCB – IOB connector If the connector is broken, shorted, or grounded, replace the connector. Replace the drum unit.
		Connect-Left PCB defective Replace the Connect-Left PCB. IOB defective Update the engine software to the latest version. Replace the IOB.