Ricoh D104 Field Service Manual page 665

Action Procedure
1. If the grainy images only appear in black image areas with Printer Full Color mode, select "CMY
+K" with the PCL printer driver. For details, see "Action 1" described below.
2. Use the A4 LEF paper. If A4 LEF paper does not solve the grainy image, check the other causes
(Cause 1, 2 and 3)
3. Change the paper size correction coefficient. For details, see "Action 4" described below.
4. Increase the amount of the toner per area (M/A). For details, see "Action 3" described below.
5. Ask a customer to change paper from high resistant paper to more smooth paper.
Cause 5: Blur Uneven Black Image
The resistance difference between the image transfer roller and image transfer belt causes the blur uneven
black image when printing a high coverage image. This symptom tends to occur especially just after
initial machine installation.
Action Procedure
1. Leave a machine for several hours if this symptom appears just after initial machine installation.
2. If the grainy images only appear in black image areas with Printer Full Color mode, select "CMY
+K" with the PCL printer driver. For details, see "Action 1" described below.
3. Decrease the target development gamma. For details, see "Action 5" described below.
4. Decrease the image transfer roller current for black and paper transfer roller current. For details,
see "Action 6" described below.
Cause 6: Grainy Image on High Resistance Small Paper
The transfer current tends to leak at the non paper area of the paper transfer roller. As a result, insufficient
transfer current causes a grainy image when using high resistance paper such as photo paper and OHP.
Action Procedure
1. Change the feeding direction from SEF to LEF.
2. Change the paper size correction coefficient. For details, see "Action 4" described below.
Cause 7: Grainy Image on OHP
The grainy image, which includes white dots, occurs when using OHP in the low temperature and low
humidity condition.
Action Procedure
• Change the environmental correction table of the paper transfer roller for OHP. For details, see
"Action 8" described below.
Troubleshooting Guide
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