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Photon Mono M7 Pro: the exposure test fails or the LCD does not display the image properly

Guide based on the manufacturer's official documentation; usi3d has not yet verified it on a machine.

Technology: Resin · Brand: Anycubic · Symptoms: The LCD screen or UV light does not light up, The resin print does not stick to the build plate, Soft, tacky or blurry resin prints · Updated on 10 October 2026

Symptom

On the Photon Mono M7 Pro nothing cures or prints come out soft or lacking detail, and in the exposure test the image seen on the LCD does not match the one on the control screen.

Likely causes, from most to least likely

  1. The LCD cable is damaged or not seated properly.
  2. The firmware is not the latest version.
  3. Cured resin on the curing screen: if the film is not replaced in time, resin reaches the screen, cures into hard-to-remove lumps and damages it.
  4. Stubborn stains on the film that spoil the LCD exposure.
  5. Exposure time not right for the resin: too short and the print is soft, lacks detail and shows layer lines; too long and it swells and loses accuracy.

Checks to tell which one it is

  • Run the exposure test in step 1 and compare the image on the paper with the one on the control screen.
  • Without the vat, look for cured resin on the curing screen or stains on the film.

Before you start

Uncured resin irritates skin and eyes: wear nitrile gloves and safety glasses, ventilate the room and do not look at the UV light. Before taking anything apart or cleaning it, switch the printer off and unplug it, unless a step says otherwise. If in any doubt, stop and ask a professional.

Step-by-step fix

  1. Run the exposure test

    Remove the resin vat and the build plate, place a sheet of A4 paper on the LCD, go to «Tools» → «Exposure Test», select the first pattern and tap «Exposure». Do not look directly at the exposed image: it can harm your eyes.

    Check: The image on the paper matches the one on the control screen.

    If that does not fix it: If it does not match, update the firmware (next step).

  2. Update the firmware

    Download the latest M7 Pro firmware from Anycubic's official website and install it on the printer.

    Check: After updating, the exposure test is correct.

    If that does not fix it: Check the LCD cable (next step).

  3. Check the LCD cable

    With the printer off and unplugged, check whether the LCD cable is damaged and reseat its connectors firmly to rule out poor contact.

    Check: The exposure test matches.

    If that does not fix it: If the cable is damaged or the image is still wrong, record a video of the test and contact the shop or Anycubic support: the M7 Pro LCD is a spare part and Anycubic has a video showing how to replace it.

  4. Clean the curing screen and replace the film

    If there is cured resin on the curing screen or the film has stains that will not come off, replace the ACF film following Anycubic's guide: the film protects the screen from resin leaks.

    Check: The screen and the film are clean and the exposure is even.

    If that does not fix it: Contact Anycubic support with photos of the screen.

  5. Tune the exposure with the R_E_R_F file

    If the LCD exposes correctly but prints come out soft or lacking detail, find your resin's exposure time with the M7 Pro's own «R_E_R_F» test file (do not rename it or use another model's file). Print its 8 models, which step the exposure up from the normal exposure, and keep the best one.

    Check: Prints come out detailed and without swelling.

    If that does not fix it: If none is good, change the file's starting exposure and repeat the test.

Prevention

  • Do not look directly at the exposure test image.
  • Replace the film when the printer prompts you or as soon as it has cured resin or stains: that protects the curing screen.
  • Keep the firmware up to date, and switch off and unplug the printer before touching cables or internal parts.

Still not fixed?

Tell usi3d's AI about your case: choose your printer, describe what you see and add photos if you like. It proposes checks step by step, with their sources.

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Printers it applies to

Anycubic Photon Mono M7 Pro.

Official sources

This guide summarises the official documentation linked here:

This guide is general information: usi3d has summarised it from the official documentation linked here, and it may not match your model, its version or its firmware. If in doubt, follow the manual and the support of your printer's manufacturer. You decide what you do with your machine, and working on it may affect its warranty.

Products that may help

Chosen for the symptoms in this guide and the printers it applies to, not for the commission. Check that they work with your printer before buying.

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