Color Shift After Transfer Unit Replacement - Ricoh B202 Service Manual

TROUBLESHOOTING GUIDE 2

4.6.3 COLOR SHIFT AFTER TRANSFER UNIT REPLACEMENT

Do the following procedure below if the color shift level is not within the target
range (max 150µm) after you replace the transfer unit and do the forced line
position adjustment (SP5-993-002 or Auto Color Registration):
Check the color shift level
1. Make sure that OPC Refresh (SP3-920-005) has been done.
2. Print out the SMC sheets (SP5-990-002).
3. Print a 1-dot grid pattern with A3/11" x 17" paper. Refer to the following table
for detailed SP mode settings:
Mode
Normal, color, 600 dpi
Normal, color, 1200 dpi
NOTE: You need to do each adjustment with the paper type normally used by
the customer.
4. Check the tendency of color shift in the grid pattern printed in step 3. At times,
a magnification scope must be used to measure the amount of color shift
between colors.
5. Go to the next step (fusing/registration roller speed adjustment) if the result is
not within the target.
Fusing/ Registration Roller Speed Adjustment
SP mode (sub-scan registration) reset
1. Make sure that the SMC sheets (SP5-990-002) have been printed out.
2. Reset the setting of SP5-993-016 to 021 to "0."
Transfer belt aging
1. Remove all PCUs. Place them on clean sheets of paper. Cover the drums with
a few sheets of paper to keep the drums away from light. Then secure the drum
positioning plate (2 screws). Then return the transfer unit release lever to the
original position.
2. Perform the transfer belt idling with SP5-804-066 (Drum M M CW) for about 3
minutes. (This stabilizes the transfer belt side-to-side movement.)
3. Reinstall the PCUs.
4. Perform adjustments (
5. Print a 1-dot grid pattern with A3/11" x 17" paper in 600 dpi mode.
6. Follow the troubleshooting guide if the color shift in the main-scan direction is
not within the adjustment standard.
B202/B178/B180
SP5-997 (Test Pattern) Setting
Tray
Pattern
selection
2 05
2 05
3.10.1).
4-74
Color mode Resolution
Full Color 600x600
Full Color 1200x1200
Paper size
(By-pass)
—
—
SM