Epson R1390 Ink + Paper Lights Keep Coming On After Parts Replaced: How to Find the Real Cause (Using Epson Adjustment Program)

Question: My Epson R1390 was great until last month, but now the ink and paper lights keep coming on. The seller sent me a new motor, ink carriage, grating strip, "devotee" strip, and waste ink pump, and I replaced everything-but they keep giving me the runaround. It's been like this since November 19th. Do you think it's something else they aren't doing?

Answer: 

Now, about your Epson R1390: when the ink and paper lights keep coming on (often flashing together), that usually indicates the printer is detecting a general/fatal condition-not a single simple "replace-this-one-part" issue. The tricky part is that multiple different failures can trigger the same light pattern, which is why parts-swapping alone often turns into an expensive guessing game. The fastest way to stop guessing is to pull the printer's stored error history and identify what the printer thinks is wrong.

Step 1: Read the stored error code using Epson's Adjustment Program

To check what's actually wrong, use a specialized Epson tool commonly called the Adjustment Program.

1. Open the Adjustment Program.

2. Select the USB port that shows your printer's name from the dropdown menu.

3. Choose Particular Adjustment.

4. Scroll and select Printer Information Check.

5. Click Check.

6. You'll see the most recent error listed at the top (usually as error number one).

That top entry matters most, because it's the last failure the printer recorded before it locked itself into the ink/paper-light condition.

If you want a quick walkthrough of this exact process, here's a short video: BCH Technologies YouTube Short (https://youtube.com/shorts/FPZzpyYuZLE)

Step 2: Interpret the "hidden" Epson error properly (the key detail most sellers skip)

Epson error reporting can be confusing because the printer may show a generic light pattern externally, while internally it stores more specific "secret" details.

For interpretation, search "BCH Epson Error" on Google-this should lead you to our page that explains Epson's Triple Secret Error Codes and how to interpret what you find inside the Adjustment Program.

This matters because two printers can both show the same blinking lights, while one is actually a carriage-position failure, and the other is a paper feed or sensor calibration failure.

What commonly causes ink + paper lights on an R1390 (even after replacing major parts)

Based on what you replaced (motor, carriage, encoder/grating strip, "devotee" strip, waste ink pump), here are the most common "something else" issues that still trigger the same ink/paper-light condition:

1) APG / carriage height sensor issues (very common after carriage work)

Many R1390 failures trace back to the APG sensor (carriage height / platen gap detection) or its mechanical alignment. Even if the carriage is new, the printer can throw an APG-related fault if:

• The sensor flag/tab isn't positioned correctly

• The carriage height mechanism is binding

• The APG sensor cable or connector is not seated fully

• The carriage can't complete its height check during startup

In Adjustment Program results, an APG sensor-related error may appear. If that shows up, focus less on "more parts" and more on alignment, free movement, and cable seating around the carriage/APG area.

2) Encoder strip installation or contamination (grating strip)

The encoder (grating) strip is extremely sensitive:

• If it's even slightly twisted, scratched, or not centered through the sensor slot, the printer can't read position correctly.

• Fingerprints, ink mist, or cleaner residue can cause misreads.

• If the strip isn't tensioned/anchored correctly, it can "walk" and cause intermittent faults.

This often presents as carriage movement errors internally, even though you already replaced "the strip."

3) CR timing belt / belt tension / carriage binding

Even with a new motor, if the belt is:

• Too tight / too loose

• Skipping teeth

• Misrouted

• Rubbing a frame edge
  ...the carriage won't accelerate/decelerate as expected, and the printer can flag a position or motion fault and throw the ink/paper lights.

Also check for physical resistance: the carriage should glide smoothly across the rail by hand (with power unplugged) without "sticky spots."

4) Ribbon cables / connectors not fully seated (or damaged)

After multiple component swaps, a very common hidden cause is simply:

• A partially seated carriage cable

• A cable inserted slightly crooked

• A cracked ribbon conductor near the bend point

• Oxidation or contamination in a connector

These can create intermittent sensor readings that look like "mystery failures," even when the replaced parts are fine.

5) Paper feed (PF) path sensor problems (even if the issue looks unrelated)

A paper-related sensor fault can also trigger ink/paper lights, especially if:

• A sensor flag is dislodged

• The PF motor can't rotate freely due to debris

• A paper sensor isn't being triggered correctly

Even if you are not actively feeding paper, the printer performs checks at startup that can trigger these errors.

6) Waste ink system and counters (pump replaced, but the logic may still lock you out)

Replacing the waste ink pump doesn't automatically clear:

• A waste ink counter limit

• A stored maintenance-related lock condition

The Adjustment Program can reveal if the printer believes it's in a waste-ink-related fault state. This is another reason reading the stored error matters more than swapping parts.

Why the Adjustment Program result is the turning point

Right now, you've been forced into a seller-led "replace parts until it works" loop. The stored code from Printer Information Check stops that loop by giving you a direction-whether it points to:

• APG sensor / carriage height

• CR movement / encoder reading

• PF movement / paper sensing

• Pump / maintenance / counter-related lock

• Or a cable/connection failure

Once you have that most recent code (error #1), troubleshooting becomes specific instead of guesswork.

Addressing printer issues can be complicated because these problems are hands-on and often depend on what we can physically observe, test, and measure. 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 there's an opening to drop off your printer. Our services are structured to repair either the whole printer or specific parts, with clear instructions on how to proceed. That said, we understand our rates aren't the most economical, so we strongly encourage self-help through online research. A great place to start 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 if we have a video for a specific issue, and after nearly a decade of creating videos, it's impossible to remember every single one-so YouTube search is the fastest method. YouTube may also recommend helpful videos from other channels that apply to your exact symptoms.

Thanks again for contacting us, and thank you for supporting BCH Technologies and our YouTube community.