How to Fix Error Code 71H on Epson L1800 DTF Printer – APG Unit and Sensor Troubleshooting

Question:

I've got an Epson L1800 DTF Printer. When I turn it on, everything works and moves, but it doesn't lock, and two lights keep blinking. I've checked everything, cleaned it, and confirmed that the motherboard is working. However, it suddenly stopped working while printing. What could be the issue, and how can I fix it?

Answer:

Thank you for contacting us. We at BCH Technologies are grateful for your engagement and support, particularly with regard to our YouTube channel. Your feedback plays a crucial role in further developing our technical expertise.

To address your issue with the Epson L1800 DTF Printer, it’s excellent that you've already utilized the adjustment software to identify the error code. Here’s a detailed guide on what the error code 71H indicates and how to fix it.

Error Code: 71H
Description: APG (Automated Platen Gap) assembly home position seeking error
Causes:

• Foreign object obstructing the sensor
• APG Unit failure (possibly due to incorrect reassembly)
• APG Sensor failure
• Cable disconnection

Steps to Fix the Issue:

1. Identify the Error Code: You've done a great job using the adjustment program. For others, it involves selecting the 'particular adjustment' option and choosing 'printer info' to display the latest error code.
2. Check the APG Sensors: The error suggests that the APG sensor isn’t receiving the correct information. There are two APG sensors, and they can easily be installed incorrectly by swapping their locations. Additionally, these sensors have tiny legs that are prone to breaking.
3. Inspect for Foreign Objects: Ensure there are no foreign objects obstructing the sensors. This can often be the simplest solution to such issues.
4. Replace Faulty Sensors: If the sensors are damaged or out of place, consider replacing them. You can find suitable replacements on our BCH Technologies website [https://bchtechnologies.com/epson-photointerrupter-widely-used-as-pe-sensor--apg--automated-platen-gap-sensor-others--l1800-1390-artisan-1430-wf-3620-wf-3640-wf-4630-wf-463x-series/].
5. Examine the APG Unit: If the sensors are intact and correctly positioned, the next step is to check the entire APG unit. This video guide on YouTube [https://youtube.com/watch?v=G_lZLqRH_f0] demonstrates how to perform this inspection.
6. Consider Replacement of the APG Unit: If the APG unit itself is faulty, you might need a replacement. We offer a no-return APG unit for the Epson L1800, available here [https://bchtechnologies.com/no-return-apg-unit-for-epson-l-1800-1390-and-artisan-1430/].
7. Also, if your printing uses rolls, it is likely there is a breakout board that re-route the APG signal. You will also need to check that board. You can do this by plug the APG sensor into the Epson's OEM sub-board, and then plug into the mainboard.

Addressing printer issues can be complex due to the hands-on nature of the problems. Consequently, we cannot provide remote troubleshooting, suggestions, or support for printer repairs. We offer in-person evaluation and repair services via our local diagnostic facility [https://bchtechnologies.com/printer-repair-service]. Given the high demand, we operate on a first-come, first-served basis. Therefore, it might take a few weeks before we can get your printer in. Our services are structured to repair either a whole printer or specific parts, with clear instructions on how to proceed if you opt for mail-in or local drop-off services. 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.

Thank you once again for reaching out. Your support helps us improve and offer better services. If you have any further questions, feel free to contact us.