How to Reroute Scanner Cables So the Scanner Lid Sits Flat (Left Hinge Binding Fix)

Question: I can't reroute the scanner cables so the left hinge lets the scanner sit flat-something feels in the way. Is there a special trick?

I'm working on rerouting the scanner's flat cable and other cables, but no matter how careful I am, the left hinge area won't let the scanner sit down flat. It feels like something is blocking it and I can't figure out what. Is there a trick to routing these cables correctly?

Answer: 

On this particular issue: I'll be honest-there isn't one magical "secret trick," and sometimes it feels easy only after you've done it a few times. In many scanner-lid assemblies, the cable path is very unforgiving: if the flat-flex cable (FFC) or harness is even slightly out of the intended channel, the left hinge will bind and the scanner won't sit flat.

What's usually "in the way" (most common causes)

Here are the most common reasons the left hinge won't close flat after re-routing scanner cables:

1. FFC not seated into the hinge's cable pocket/channel

   • Most lids have a molded guide or "tunnel" that the cable must sit inside.

   • If the FFC rides on the edge of that guide (even by 1-2 mm), the hinge will pinch it and the lid will rock upward.

2. Cable fold is too thick at the hinge

   • If the FFC is folded sharply or doubled over at the hinge pivot area, it becomes a "spacer" that physically prevents the hinge from closing.

   • The correct routing is usually a gentle bend radius, not a tight crease.

3. Harness twist or wrong side of the hinge pivot

   • If the cable bundle crosses the hinge pivot in the wrong direction, it can get trapped behind the hinge arm.

   • Even if it doesn't pinch, it can force the hinge to sit slightly open.

4. Cable not fully tucked under clips or foam pads

   • Many scanner lids use small clips, adhesive foam, or tape to keep the cable flat.

   • If the cable pops above the clip/tape edge, the hinge area won't settle.

5. Misalignment of the hinge itself

   • Sometimes the hinge isn't seated all the way into its mounting points. Then it looks like a cable problem, but it's actually hinge geometry.

6. Foreign object or displaced part in the hinge cavity

   • A common culprit is a foam pad shifted out of place, a cable grommet not seated, or a small screw that fell into the hinge pocket.

A practical "no-mystery" method that usually works

Try this approach-it's simple, repeatable, and helps reveal exactly where the interference is happening:

1. Open the scanner lid and remove slack

   • You want enough slack for lid movement, but not so much that the cable bulges near the hinge.

   • The cable should lie flat and "float" through the hinge path.

2. Route the FFC flat first, then add the secondary cables

   • If you route the thicker harness first, it often blocks the correct path for the FFC.

   • The FFC typically belongs closest to the plastic channel surface (flattest layer).

3. Follow the molded channel from the scanner head toward the hinge

   • Don't "free-route" it. The lid plastics are usually designed so the cable naturally falls into the correct channel when aligned.

4. Use a gentle S-curve near the hinge

   • Instead of a tight fold, aim for a smooth curve that can flex as the lid opens/closes.

   • Tight folds = thicker stack = hinge won't sit flat.

5. Close-test in stages

   • Lower the lid slowly and watch the left hinge area.

   • If it starts to lift or rock, stop and look at which section of cable is buckling upward. That spot is your interference point.

6. Look for pinch marks

   • If the hinge is catching the cable, you may see a shiny rub line, a crease beginning, or the cable trying to "walk out" of the channel.

   • Do not force it-pinched FFCs can crack traces and cause intermittent scanning errors later.

What you should not do

• Don't force the lid closed if it doesn't sit flat. If the hinge is fighting the cable, the cable is the thing that loses.

• Don't sharply crease the FFC to "make it fit." It might close today, but the cable can fail later from repeated flexing at the crease.

About error codes

You didn't mention any error codes in your question, so I can't responsibly name specific scanner-related codes for your case. If you are seeing an error code (for example, a scanner/ADF initialization error, carriage-related error, or a "scanner unit" error message), include the exact code and printer model, because different models interpret scanner/hinge/FFC faults differently.

Addressing printer issues can be complicated because so much of it is hands-on and depends on what's physically happening inside the unit. Because of that, we're not able to provide remote troubleshooting, suggestions, or support for printer repairs. We do offer an in-person evaluation and repair service through our local diagnostic facility: Printer Repair Service (https://bchtechnologies.com/printer-repair-service). Due to high demand, we operate first-come, first-served, and it may take a few weeks before you're able to drop the printer off. Our services are structured to repair either an entire printer or specific parts, with clear instructions on how to proceed. That said, we recognize our rates aren't the most economical, so we strongly recommend self-help through online research. A great starting point is YouTube-especially our channel homepage: BCH Technologies on YouTube (https://youtube.com/@bchtechnologies). Use the search icon next to "About" on the right side of the menu bar to find videos by topic. I receive dozens of messages each day asking for a video on a specific issue, and after creating videos for years, it's difficult to remember every single one-YouTube search is the fastest way. Plus, YouTube may also recommend helpful videos from other channels that match your exact situation.

Thanks again for reaching out, and I appreciate your patience. I hope this helps you get the cable seated properly so the left hinge can close and the scanner sits flat the way it should.