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April, 2007 SERVICE CALL CONDITIONS
4-43
SC420 C Potential sensor error 1: Vd Adjustment K
SC421 C Potential sensor error 2: Vd Adjustment M
SC422 C Potential sensor error 3: Vd Adjustment C
SC423 C Potential sensor error 4: Vd Adjustment Y
The development potential of
the drum before exposure (Vd)
cannot be adjusted to within
±10 V of the target voltage (-
900V).
• Toner density low
SC424 C Potential sensor error 5: Vl adjustment K
SC425 C Potential sensor error 6: Vl adjustment M
SC426 C Potential sensor error 7: Vl adjustment C
SC427 C Potential sensor error 8: Vl adjustment Y
Vpl could not be adjusted to
within ±10V of the target Vpl
after exposure of the ID sensor
patterns.
• Toner density low
SC432 C Potential sensor error 1: Vr K
SC433 C Potential sensor error 2: Vr M
SC434 C Potential sensor error 3: Vr C
SC435 C Potential sensor error 4: Vr Y
Vr > 200V
The residual voltage (Vr), the amount
of voltage that remains on the surface
of the drum after the Quenching Lamp
fires is greater than 200V.
• Toner density low
SC436 D Potential sensor error 5: Vd K
SC437 D Potential sensor error 6: Vd M
SC438 D Potential sensor error 7: Vd C
SC439 D Potential sensor error 8: Vd Y
The VdHome reading, the first step of
the process control self-check,
detected that the development
potential of the unexposed areas of
the drum are not within the prescribed
range (-500 to -700)
• Potential sensor dirty
• Potential sensor defective
• Charge roller defective
• Charge power pack defective
• OPC defective