About the timing strip

The timing strip is a clear, plastic strip approximately 1/4" in height positioned horizontally across the center of the unit, just in front of the carriage drive belt. The timing strip contains many thin black vertical lines that help determine the carriage position during operation.

How it can get dirty
During certain uncommon tasks such as the removal of a paper jam, it is possible to inadvertently touch a lubricated area on the printer's chassis causing a small amount of grease to be deposited onto the timing strip.
 

Symptoms of a dirty timing strip
Grease on the timing strip may result in poor print quality including; mis-aligned or distorted characters, vertical lines or, in some cases, an inoperable error condition (such as 5100) or knocking / grinding noise.

Clean the timing strip

In most cases, it is easy to remove the grease from the timing strip using common household items. If you wish, you may follow the steps below to remove the grease from the timing strip.

• Clean, unused cotton swab

• Small amount of Isopropyl Alcohol or window cleaner

• Flashlight or other light source

Steps

1. Make sure that the power is turned on.

2. Retract the paper output tray and the output tray extension.

3. Open the cover.
   The FINE cartridge holder moves to the replacement position.

   

4. With the cover open, unplug the power cord from the wall outlet or power strip.
   Note: check the printer's power LED is no longer illuminated.

5. Hold the top of the FINE cartridge holder and slide it slowly to the right edge.

6. When the carriage is to the far right, you will be able to see the timing strip.

   

7. Using a flashlight, carefully inspect the timing strip for grease and dirt. It is helpful to view the timing strip from several angles as even a small amount of grease can impact print quality.

   

   The timing strip is a clear strip located in front of the drive belt.

8. Moisten the cotton swab with Isopropyl alcohol (or window cleaner), and carefully remove the grease from the timing strip.

   Note: do not touch or remove grease from the chassis (metal rail).

9. Once you have confirmed that the left and center portions of the timing strip are clean, gently slide the carriage all the way to the left.

10. Inspect the right side of the timing strip until and wipe it with the cotton swab until it is completely free of grease and dirt.

11. Gently close the cover.

    

12. Reconnect the power cord and power on the printer.
    (The indicator light blinks steadily while the printer initializes.)

13. Print a test document and photograph. If print quality is still poor, repeat the above steps.

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