ProColored Printer Has Power but Won't Turn On After Printhead Replacement: Causes and Troubleshooting Guide

Question

I was replacing the printhead on my ProColored printer, but after the replacement, the printer would not print. I turned the printer off, and now it will not turn back on. There is still power going to the printer. What could be causing this, and what should I check?

Answer

In your case, since this happened after changing the printhead, the most likely issue is not simply a normal power failure. It is more likely related to the printer's internal electronics, the printhead connection, or the FFC ribbon cable.

A ProColored DTF printer is usually made up of two major systems. The first is the printer section itself, which includes the Epson-based printer engine, carriage, printhead, mainboard, power supply, carriage motor, sensors, and ribbon cables. The second is the ink system, which may include the white ink circulation system, mixer or stirrer, dampers, ink pump, waste ink system, and sometimes extra parts such as a heating platform, vacuum platform, or film-feeding components.

The rear main power switch may provide power to both systems, but that does not always mean the printer section is actually powering up correctly. In many cases, the ink system may still run while the printer itself remains dead. For example, you may hear the white ink mixer, circulation pump, fan, or heater turning on, but the printer's control panel, carriage, and printer electronics do not respond. This often points to a problem in the printer's mainboard, printhead circuit, FFC cable, or internal power delivery to the printer section.

Since the issue started after printhead replacement, the first thing I would suspect is a short circuit involving the printhead or the FFC cable. The printhead is one of the most sensitive and expensive electronic components in the printer. If the printhead cable is installed backward, crooked, partially inserted, contaminated with ink, or damaged, it can short the mainboard as soon as the printer is powered on. Once that happens, the printer may stop turning on even though the external power switch and ink system still appear to have power.

The FFC cable should be checked very carefully. Look for bent contacts, burned marks, ink contamination, torn edges, corrosion, or any section that looks darker than normal. Even a tiny amount of ink on the contact end can create a short. Also check whether the cable was fully inserted into the printhead connector and mainboard connector. If the cable was inserted at an angle or not locked properly, the pins may not line up correctly. That can damage the printhead, the cable, the mainboard, or all three.

The next item to check is the printhead itself. If the printhead was defective, incompatible, previously damaged, or installed while the printer still had residual power, it may have shorted internally. A printhead short can prevent the printer from booting. In some cases, it can also blow a fuse on the mainboard or damage the printhead driver circuit. Unfortunately, once the mainboard is damaged, replacing only the printhead may not bring the printer back.

You should also inspect the mainboard for visible damage. Look for burned components, blown surface-mounted fuses, dark spots, melted areas, or a burnt electronics smell. Some printer boards have tiny fuses marked with labels such as F1, F2, F3, or similar. If one of those fuses is open, the printer may not power on. However, a blown fuse is usually a symptom, not the root cause. If the fuse blew because of a shorted printhead or bad FFC cable, replacing the fuse without fixing the short can cause the same failure again.

Another important point is the power supply. Since you mentioned that the printer still has power, the power supply may not be completely dead. However, some printers have more than one voltage rail. One part of the machine may receive power while another part does not. For example, the ink system may receive 12V or 24V power, while the printer logic board may not be receiving the correct voltage. If you are comfortable using a multimeter, you can test the power supply outputs, but be careful because printer power supplies can be dangerous if handled incorrectly.

Here is the general order I would check:

First, unplug the printer completely from the wall and let it sit for a while so any stored charge can discharge. Do not keep trying to power it on repeatedly, because if there is a short, repeated power attempts can make the damage worse.

Second, inspect the printhead FFC cable. Remove it and check both ends closely. If there is ink, corrosion, burning, or bent contacts, do not reuse it. FFC cables are relatively inexpensive compared with a printhead or mainboard, so if there is any doubt, replacing the cable is safer.

Third, inspect the printhead connector. Look inside the connector on the printhead and on the board side. If ink got into the connector, that can cause a short. Do not power the printer back on until the connection area is clean, dry, and confirmed safe.

Fourth, inspect the mainboard. If the printer will not turn on at all after a printhead replacement, the mainboard may be burned. This is especially likely if the printer was powered on with a misaligned or contaminated printhead cable.

Fifth, check the printhead. A shorted printhead can damage the mainboard, and a damaged mainboard can damage a new printhead. This is why replacing parts randomly can become expensive. If the mainboard and printhead are both questionable, installing a new printhead on a bad board can destroy the new printhead immediately.

For this particular situation, I would mainly suspect one of these three areas: the mainboard, the FFC cable, or the printhead. The most common chain of events is that the printhead or FFC cable was not connected correctly, which caused a short, and then the mainboard failed. Another possibility is that the printhead was already defective or electrically shorted, and once installed, it damaged the printer electronics.

Because your printer does not turn on after the printhead replacement, this is probably beyond a basic clogging or print-quality issue. This is more of an electrical troubleshooting issue. If the machine has separate ink-system power and printer-board power, the fact that the ink system still runs does not prove that the printer's mainboard is healthy. It only proves that some part of the machine is still receiving power.

Addressing printer issues can be a complicated process because many repairs require hands-on inspection. For that reason, we are not able to provide remote troubleshooting, repair suggestions, or step-by-step support for individual printer repairs. We do offer an in-person evaluation and repair service through our local diagnostic facility: BCH Technologies Printer Repair Service [https://bchtechnologies.com/printer-repair-service]. Because demand is high, repairs are handled on a first-come, first-served basis, so it may take a few weeks before we can accept your printer for drop-off. Our repair service can evaluate either the whole printer or specific parts, and the instructions on the service page explain how to proceed. However, we understand that our rates may not be the most economical option for everyone. For that reason, we strongly recommend self-help through online research whenever possible. A good starting point is YouTube, including our channel homepage at BCH Technologies on YouTube [https://youtube.com/@bchtechnologies]. Once you are on the channel page, use the search icon next to "About" on the right-hand side of the menu bar to search for specific repair topics. I receive dozens of questions every day asking where to find videos on certain issues. Since we have created videos for more than nine years, it is difficult to remember every single one, so YouTube's search function is usually the fastest way to locate the most relevant video. YouTube may also recommend helpful videos from other creators that apply to your situation.

Thanks again for reaching out and for supporting our channel. I hope this gives you a better idea of where to start: check the mainboard, inspect or replace the FFC cable, and be very careful with the printhead before powering the printer again.