Solved: Canon MX922 Copies Have Wavy, Zigzag Text or Double-Line Images – Causes and Fixes

Question:

Why does my Canon MX922 produce wavy or double-line images and zigzag text when copying, but prints perfectly fine from my computer? The distortion appears whether I use the flatbed glass or the document feeder.

Answer:

Understanding the Problem

When a printer like the Canon MX922 prints well from a computer but produces distorted or smudged copies from the scanner—whether using the flatbed or Automatic Document Feeder (ADF)—the root cause typically lies in the scanning mechanism, not the ink system or printhead.

In your case, the issue is likely not related to hardware failure in the printing subsystem. Rather, it's caused by problems in the scanning optical path, particularly:

• Dirty scanner glass or ADF strip: Canon printers have two scanning areas—one large platen for flatbed scans and a narrow strip for scanning from the ADF. Even a tiny smudge, speck of dust, or fingerprint on either surface can cause lines to appear wavy, double, or ghosted.

• Misaligned scanner unit: If the scanner rail under the glass is slightly out of alignment, especially from impact or heavy use, the scan data might be distorted before it’s sent for printing.

• Scanner light calibration issues: The scanner head uses a calibration strip (usually white) to set reference brightness and alignment. If this strip is dirty or damaged, it may incorrectly process the scanned image, resulting in doubled or offset text.

Recommended Fixes

1. Thoroughly Clean the Scanner Glass and ADF Strip:

   • Use a soft, lint-free microfiber cloth.

   • Apply a small amount of glass cleaner (like Windex) to the cloth—never spray directly on the glass.

   • Wipe both the large flatbed glass and the thin strip used by the ADF, usually located on the left-hand edge of the glass.

   • Look at the glass at a shallow angle with a flashlight to reveal oil smudges or fine debris that might be invisible under normal lighting.

2. Clean or Inspect the White Reference Strip:

   • This strip is typically located underneath the scanner lid.

   • Dirt or yellowing can affect scanner calibration.

   • Gently clean it using the same lint-free cloth and glass cleaner.

3. Run a Copy Test Again:

   • Try copying the same document using the flatbed and ADF.

   • If the issue clears, it was likely due to residual debris.

4. Update the Printer Firmware:

   • Although rare, firmware issues can sometimes impact scan performance or introduce minor calibration glitches.

   • Visit Canon’s support website (https://www.usa.canon.com/support) to download the latest firmware for the MX922.

5. Perform a Scanner Alignment Test (if available):

   • Some Canon models offer a scanner calibration feature in the maintenance settings.

   • Refer to your user manual or Canon's support site for model-specific steps.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. So, we're not able to provide remote troubleshooting, suggestions, or support for printer repairs. We offer an in-person evaluation and repair service via our local diagnostic facility (https://bchtechnologies.com/printer-repair-service). Given the high demand, we operate on a first-come, first-served basis. So, it might take a few weeks before we can get your printer to drop it off. Our services are structured to repair either a whole printer or specific parts, with clear instructions on how to proceed. However, we acknowledge that our rates aren't the most economical. Thus, we highly recommend that you resort to self-help via online research. You can start by checking out YouTube or visiting our YouTube channel's homepage (https://youtube.com/@bchtechnologies). Look for specific videos using the search icon next to "About" on the right-hand side of the menu bar. I receive dozens of queries every day asking about videos for specific topics. Having created videos over the past nine years, it's challenging to remember every single one. Therefore, using YouTube's search function would be most efficient. Plus, YouTube might suggest relevant videos from other channels that could assist you.

Thanks again for reaching out, and for your ongoing support of BCH Technologies. We’re here to empower you with the tools, knowledge, and guidance you need to keep your printer running smoothly.