Procolored L1800 Not Turning On, White Ink Dropouts, and Blinking Lights: What the Symptoms Mean and What to Do Next

Question: I bought a used Procolored L1800 and it's always struggled to print white ink consistently. I've had low white coverage, the paper light coming on a lot, and sometimes both the page and ink lights come on (I reset the waste ink and it works briefly). Lately it won't print at all-the job doesn't even show up in the queue. After cleaning around the printhead/cap area and cleaning the head with solution, it worked briefly, but when I reinstalled the printhead and tightened screws, the carriage started "creeping" instead of moving normally and I heard an unusual beep/tone. Now the control panel won't turn on at all. I checked the F1/F2/F3 fuses and MOSFET like in your video; I see power at the fuse but some transistors don't. I purchased BCH mainboard repair service and I'm in California, so I'll ship the motherboard. I already removed the board screws and need to disconnect cables. I also ordered a fuse and a manifold because I thought it was the fuse-until I realized I'd need to solder. How should I proceed, and what should I do with the printer in the meantime (vacation mode)?

Answer: 

Based on your symptoms, you're dealing with more than one problem. The "control panel won't turn on" portion is strongly tied to the mainboard power section, but several of the earlier issues (white dropouts, paper light behavior, waste ink indications, and jobs not reaching the queue) can be caused by maintenance station, ink delivery, sensor/firmware, driver/spooler, or carriage/mechanical issues-not strictly the mainboard.

Below is a clear breakdown so you know what we can fix with the mainboard repair, what may remain afterward, and what to do right now.

1) Why the control panel won't turn on (mainboard power fault is likely)

When the control panel is completely dead, it usually points to a failure in the mainboard's power regulation path (for example: protective fuse(s), MOSFETs, voltage regulators, or a short downstream that causes protection shutdown).

You mentioned checking F1 / F2 / F3 and the MOSFET, and that "the fuse seems to have power but a couple transistors do not." That pattern is consistent with one of these scenarios:

• A failed MOSFET or regulator preventing proper downstream rail generation.

• A shorted component on the board or a short coming from a connected assembly/cable that causes the board to shut down or brown out.

• Aftermarket/remanufactured fuse modifications that can introduce instability.

Important note about fuses on these boards

On many Epson-based boards, there is one primary, correct fuse for the circuit, and we often see remanufactured/refurbished boards with extra "added" fuses or non-original fuse work. Those additions are frequently unnecessary and can actually create new intermittent power issues.

What we will do on our end: since you ordered mainboard repair, we'll focus on restoring proper power-up behavior and removing problematic remanufacturer "extras" (including unnecessary fuse modifications) if present. The goal is a stable board that powers on normally.

2) The "creeping carriage" and the beep/tone: what it suggests

The carriage "creeping" (slow/struggling movement) right after reinstalling/tightening around the head area is a big clue. It can happen if:

• The carriage is binding mechanically (something tightened too much, a harness pinched, the head not seated correctly, or the carriage cover/contacting parts).

• A dragging cable/hose is catching.

• The CR (carriage) motor or driver circuit is struggling due to resistance or an electrical issue.

• The printer detects abnormal movement and triggers an error tone before shutting down.

Even a brief bind can stress electronics. If there was a short or overload event (for example, a pinched cable, damp connector, or a component contacting where it shouldn't), it can contribute to mainboard failure.

3) Your earlier light patterns and what they commonly mean (and why they may return after mainboard repair)

You mentioned:

• Low white coverage

• Paper light frequently on

• Both page and ink lights on and waste ink reset only helps briefly

• Not printing / job not showing in queue at all

• White stops again after cleaning

These symptoms can come from multiple layers, and it's common for more than one to be present in white-ink conversions:

A) Low white coverage / white inconsistency

Most commonly from:

• Partial clogs in the white channels (white ink settles and clogs faster than CMYK).

• Air leaks in white ink lines, dampers, manifolds, or fittings.

• A failing damper, weak suction, or a cap top that isn't sealing well.

• Maintenance station problems (cap top not sealing, pump weak, wiper/cap contamination).

Cleaning the cap/cover area and seeing improvement supports the idea that the capping station / cap top seal / suction is part of the story.

B) "Paper" light frequently on

Often related to:

• Paper feed sensing (paper sensor, skew, feed path issues).

• Sometimes a false paper detection due to debris, sensor contamination, or mechanical timing issues.

C) "Page + ink" lights together and waste ink resets that only work briefly

This often points to a waste ink counter or maintenance-related detection behavior. Resetting it may clear the alert temporarily, but if there's an underlying maintenance station issue (excess purge cycles, ink pooling, pump issues, or incorrect waste routing), the printer can reach the threshold again quickly.

D) Print job doesn't show up in the printer queue

That one can be software/connection rather than hardware:

• Windows/Mac spooler issue

• Wrong port selected

• Driver corruption

• USB cable / hub issue

• A RIP workflow issue (common in white-ink setups)

• If the printer is in a hard error/offline state, the OS may not send the job normally

So yes-some of your problems are not strictly "mainboard problems." We will repair what you paid for (the board power-up issue), but you may still need to address the white ink delivery + maintenance station side afterward.

How to proceed with the mainboard shipment (and what to do in the meantime)

Step 1: Remove the mainboard carefully (your plan is correct)

Since you've already unscrewed the mainboard and just need to remove cables:

• Unplug the printer from the wall and let it sit a few minutes before touching connectors.

• Take clear photos of every connector before you remove it (your phone is perfect for this).

• Remove cables by gripping the connector housing, not pulling on wires.

• If any connector feels stuck, gently wiggle-don't pry hard.

Step 2: About the fuse you ordered

It's totally understandable to assume "fuse = no power." However, in many cases:

• The fuse is not the root cause, or

• The board has been modified with extra fuse work that creates more issues.

So don't worry-once we have your board, we'll correct the power path properly. If there's a remanufacturer fuse modification, we will remove what isn't needed and stabilize the circuit.

Step 3: What to do with the printer while the mainboard is out ("vacation mode")

Because your printer can't power on, the priority is preventing the printhead from drying out while it sits.

Best interim storage method (recommended):

1. Fill the capping station (cap top) with distilled water (or a safe storage/cleaning fluid if you already use one that is known compatible with your inks and seals).

2. Park the printhead on the capping station so the nozzle plate stays sealed and moist.

3. Shut the printer down (or leave it powered off since it already is).

4. Then proceed with removing/shipping the mainboard (which you're already doing).

This is the safest "vacation mode" approach when a printer cannot run its normal maintenance routines.

Important caution: Avoid leaving white ink systems sitting dry for long periods. White ink settles quickly and can hard-pack in lines/dampers if the system is neglected. If you'll be down for a while, keeping the head properly parked and sealed is the most important thing you can do.

After the mainboard is repaired: what you may need to tackle next

Once the board powers on again, if the white problem returns, the next most common root causes are:

• Cap top not sealing (nozzle plate not getting proper suction)

• Weak pump

• Dampers/manifold issues (you already ordered a manifold, which can help if there's restriction or contamination)

• Air leaks on the white line (fittings, dampers, cracked tubing, loose clamps)

• White ink management (agitation/recirculation if your setup has it, and consistent use)

We'll get you past the "won't turn on" issue first. Then you can evaluate what remains with the machine powered and able to report symptoms normally.

Addressing printer issues can be a complicated affair because these problems are hands-on and often require physical testing. 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 on a first-come, first-served basis, and it may take a few weeks before we're able to receive your printer for drop-off/service. Our services are structured to repair either an entire printer or specific parts, with clear instructions on how to proceed. That said, we acknowledge our rates aren't the most economical, so we strongly recommend self-help through online research when possible. A great place to start is YouTube, including our channel homepage: BCH Technologies on YouTube (https://youtube.com/@bchtechnologies). Please use the search icon next to "About" on the right side of the menu bar to find videos by topic. I receive dozens of questions every day asking for specific videos, and after creating content for years, it's hard to remember every single one-YouTube's search tool is the fastest way to locate the most relevant guidance. It may also recommend helpful videos from other creators that match your exact symptoms.

Thank you again for your support and for trusting us with your repair. Once the mainboard is shipped, you're doing the right thing by protecting the head with a properly filled cap and keeping it parked. We genuinely appreciate you being part of our community and supporting the work we do.