Ricoh MP C6502SP Field Service Manual page 1387

If the symptom occurs at 40mm intervals:
• If there are scratches on the charge rollers, replace the affected roller(s).
• If there are no scratches, wipe the surface of the roller with a damp cloth and then with a
dry cloth.
Troubleshooting for White Spots in Low-Temperature, Low-Humidity Environment
Symptom
1. Under the weight of Plain Paper 2: White spots may appear on the 2nd page of duplex
printing when using the paper with unsmooth surface and high electric resistance in LL
environment.
2. Higher than weight of Middle Thick Paper: White spots may appear on paper with unsmooth
surface and high electric resistance. (See sample image below)
Cause
1. The electrical resistance increases when the paper goes through the fusing roller and the
moisture of the paper evaporates.
2. Due to high electrical resistance characteristics of the paper.
Action
Lower transfer current by changing the following SP
Only change the paper type and thickness that the user needs to use.
D135/D136/D137/D138
SP No.
SP2-641-001 to 078
SP Name
PTR Bias:BW
Image Quality
1385