Ricoh IM 550F

6.Troubleshooting
549
Service Call 490-491
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 (PCB20) defective
• IOB (PCB17) defective
• Toner density sensor defective
1. Reconnect the following connectors.
• Toner Density Sensor – Drum PCB (PCB10) connector
• Drum PCB (PCB10) – Drum Connection PCB (PCB11) connector
• Drum Connection PCB (PCB11) – Connect-Left PCB (PCB20)
connector
• Connect-Left PCB (PCB20) – IOB (PCB17) connector
2. If the connector is broken, shorted, or grounded, replace the connector.
3. Check that the gears and rollers of the development unit are not
damaged and rotate smoothly.
4. Replace the development unit.
• Toner motor defective
1. Check the drive gears can rotate or they are not unusually loaded. If
necessary, replace the drive gear.
2. Reconnect the following connectors.
• Toner Density Sensor – Drum PCB (PCB10) connector
• Drum PCB (PCB10) – Drum Connection PCB (PCB11) connector
• Drum Connection PCB (PCB11) – Connect-Left PCB (PCB20)
connector
• Connect-Left PCB (PCB20) – IOB (PCB17) connector
3. If the connector is broken, shorted, or grounded, replace the connector.
4. Replace the drum unit.
• Connect-Left PCB (PCB20) defective
Replace the Connect-Left PCB (PCB20).
• IOB (PCB17) defective
1. Update the engine software to the latest version.
2. Replace the IOB (PCB17).