Troubleshooting Non-Responsive Projecta Display PMLCD and PMLCD-BT

Troubleshooting Non-Responsive Projecta Display PMLCD and PMLCD-BT

Troubleshooting a Non-Responsive Projecta PM300BT Display Screen



Applies To

Product: Projecta PM435, PM235 Power management System
Display part number- PMLCD and PMLCD-BT
Issue: Display powers on, but buttons do not respond
Common Symptoms: No button response, frozen screen, water pump/load buttons not working, screen appears active but cannot be controlled

FAQ

1. My Projecta display screen is on, but none of the buttons work. What should I do first?

First, check whether the display is receiving power and showing any information on the screen.

Please check:

  • Is the screen lit up?
  • Can you see battery level, time, system status, or any other display information?
  • Does the screen flicker, dim, freeze, or remain stuck on one screen?
  • Are all buttons unresponsive, or only some buttons?

If the screen is powered but the buttons do not respond, the issue may be with the display screen, connection, or internal button circuit.


2. Does a non-responsive screen always mean the display is faulty?

No. A non-responsive screen does not always mean the display has failed.

Possible causes include:

  • Loose connection behind the display
  • Poor power supply or blown fuse
  • Loose or damaged communication cable
  • Software or firmware glitch
  • Display button failure
  • Internal display hardware fault

The screen should be checked before replacement is arranged.


3. What should I check if the screen is completely blank?

If the screen does not turn on at all, check the power supply before assuming the display is faulty.

Please check:

  • The caravan battery has charge
  • The display power cable is connected correctly
  • The relevant fuse is not blown
  • The main Projecta power system is switched on
  • There are no loose plugs behind the display

If the screen remains blank after these checks, contact support or your dealer for further assistance.


4. What should I check if the screen is powered but frozen or not responding?

If the screen is on but the buttons do not work, try the following


Turn the system off if safe to do so.

Wait 1–2 minutes.

Turn the system back on.

Check whether the buttons respond after restart.

Check whether the display cable is firmly connected behind the screen.

Check whether the system can be controlled using the Bluetooth app.

If the screen still does not respond, the display may require replacement.


5. Can I still use the system if the display buttons are not working?

In some cases, yes.

If the PM300BT Bluetooth app can still control the water pump and load functions, the main system may still be operating correctly. This usually means the issue is isolated to the physical display buttons or the display screen itself.

Example:

  • App can turn the water pump on/off
  • App can control load output
  • Display screen is powered
  • Display buttons do not respond

In this situation, the display screen is likely faulty and may need to be replaced.


6. How do I test whether the app still works?

Open the compatible Projecta Bluetooth app and check whether you can control the system.

Test the following:

  • Can you connect to the PM300BT?
  • Can you turn the water pump on or off?
  • Can you control the load output?
  • Does the app show battery or system information?

If the app works but the screen buttons do not, this information is helpful for confirming the display screen fault.


7. What information is needed before a replacement can be arranged?

To avoid delays, please provide the following information:

  • Display screen part number
  • Display screen serial number
  • Clear photo of the label on the back of the display
  • Photo or video showing the screen powered on
  • Confirmation that the buttons do not respond
  • Confirmation whether the Bluetooth app can control the pump and load
  • Proof of purchase, if requested
  • Customer delivery details

This information helps confirm the correct replacement part and avoids compatibility issues.


8. Where do I find the part number and serial number?

The part number and serial number are usually located on the label on the back of the display screen.

To locate them:


Carefully remove the screen from the wall mount.

Do not pull hard on the wiring.

Take a clear photo of the rear label.

Make sure the part number and serial number are readable.

If the screen is difficult to remove, contact your dealer or service provider for assistance.


9. Why do I need to provide a photo of the back of the screen?

A photo of the rear label confirms the exact model and serial number of the display.

This is important because different Projecta display screens may look similar but may not be interchangeable. Supplying the correct part and serial number helps ensure the correct replacement screen is provided.


10. What if the buttons are not working but the app controls everything correctly?

If the app can control the pump and load, but the physical display buttons do not respond, the main system is likely functioning correctly.

This usually points to an issue with the display screen itself, such as:

  • Failed button circuit
  • Internal display fault
  • Damaged keypad interface
  • Display firmware issue

If power and app operation are confirmed, a warranty replacement may be required.


11. What if neither the screen buttons nor the app work?

If both the screen buttons and app control do not work, the issue may not be limited to the display screen.

Possible causes include:

  • Main power system fault
  • Battery or fuse issue
  • Communication fault
  • Incorrect wiring
  • Control board issue
  • Bluetooth pairing issue

In this case, further diagnosis may be required before replacing the display.


12. Should I replace the display immediately?

Do not replace the display until basic checks have been completed.

Before replacement, confirm:

  • The screen has power
  • The buttons are still unresponsive after restart
  • The wiring behind the display is secure
  • The Bluetooth app test has been completed, if available
  • The part number and serial number have been recorded

If these checks confirm the display is powered but still not responding, replacement may be the correct next step.


After-Hours Troubleshooting Checklist

If the issue occurs outside business hours, try the following checks before contacting support:

Step 1: Check power

  • Confirm the caravan battery has charge.
  • Check the main power switch.
  • Check relevant fuses.
  • Confirm the display is lighting up.

Step 2: Restart the system

  • Turn the system off if safe.
  • Wait 1–2 minutes.
  • Turn the system back on.
  • Recheck the display buttons.

Step 3: Check the display connection

  • Carefully remove the display from the wall mount.
  • Check that the cable is firmly connected.
  • Look for any damaged, loose, or bent connectors.
  • Refit the screen carefully.

Step 4: Test the app

  • Open the Projecta Bluetooth app.
  • Confirm whether the app connects.
  • Try turning the water pump and load on/off.
  • Note whether the app works even though the screen buttons do not.

Step 5: Take photos/videos

Before contacting support, take:

  • A photo of the powered display screen
  • A short video showing the buttons not responding
  • A photo of the rear label showing part number and serial number