Troubleshooting for vertical streaks caused by contact with the toner adhering to the guide plate

Symptom

Vertical streaks appear.

Condition

Scratches tend to stand out when printing on relatively stiff thick coated paper.

Cause

After fusing, paper comes into contact with small convex scratches or adhering toner on the guide plate and vertical streaks appear.

Action (overview)

1. If the problem occurs at the position of the ribs of the heat pipe entrance guide plate, clean the heat pipe entrance guide plate ribs.
2. If the problem occurs in other places, clean the paper transport path/duplex unit.
3. If cleaning does not improve the situation, lower the fusing temperature.

Action (detail 1): Clean the heat pipe entrance guide plate ribs.

Position of the heat pipe entrance guide plate ribs [A]

Action (detail 2): Clean the paper exit transport path/duplex unit.

• If streaks appear on straight-fed one-sided prints or the second side of two sided prints: (1) Clean the upper part of the Paper Exit transport path.
• If streaks appear on the first sides of two-sided prints: (2) Clean the lower part of the Paper Exit transport path.
• If streaks appear on inverted one-sided prints: (3) Clean the lower left part of the Paper Exit transport path.
• If streaks appear on the second side of two-sided prints: (4) Clean the duplex unit.

1. Upper part of the paper exit transport path
   
   
   [A]: Paper Exit Upper Guide Plate
2. Lower part of the paper exit transport path
   
   [A]: Fuser Exit Guide Plate
   [B]: Heat Pipe Entrance Guide Plate
   [C]: Paper Exit Junction Gate
   [D]: Transport Ribs (22 positions)
   [E]: Paper Exit Guide Plate (Clean this area thoroughly.)
3. Lower left part of the paper exit transport path
   
   [A]: Paper Exit Lower Left Guide Plate (Clean this area thoroughly.)
   [B]: Paper Exit Lower Right Guide Plate
   [C]: Junction Gate Ends
4. Duplex unit
   
   [A]: Duplex Transport guide plate (Upper) (Clean the turning point on the right thoroughly.)
   [B]: Duplex Transport guide plate (Lower)

Action (detail 3): Lower the fusing temperature.

Enter SP mode and lower the fusing temperature with SP1-984. (Guideline: Lower it 10° C at a time.)

Reference

The following features are unique to this machine that contribute to the vertical streaks.

• Chances of foreign materials to scratch the prints are high because the toner used for this series has a low melting point.
• Paper contacts the guide plate after fusing because the curve of the switchback exit path is tight.

Comparison with MPC7501/6501

Advantage: Curvature

Disadvantage: Support for thicker paper, Toner

Comparison with ProC751EX/651EX

Disadvantage: Support for thicker paper, Toner

Layout of the fusing exit paper path

[A]: Cooling roller

[B]: Fusing