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[LG Projector] An error message or "No Signal" message appears on

If messages such as "Network Error," "No Signal," or "Authentication Failed" appear on your TV screen, it is usually caused by a set-top box signal issue or a poor cable connection rather than a TV malfunction. First, try turning the set-top box off and on again. If the issue persists, contact your set-top box service provider to request a signal check.

[LG Projector] An error message or "No Signal" message appears on the set-top box LG USA help image
TroubleshootingTVs

What to Check First

  1. Temporary set-top box error: The set-top box system may become unstable due to prolonged use.
  2. Disconnected network: The internet (LAN) cable may be unplugged, or there may be an outage with your service provider.
  3. Poor cable connection: The HDMI cable connecting the TV and the set-top box may be loose.
  4. Service subscription issues: Broadcasting may be suspended due to unpaid bills or delayed activation.
  5. 1. Locate the set-top box behind or below your TV.
  6. 2. Turn the power switch on the back of the set-top box off and on, or unplug the power cord and plug it back in after 1 minute.
  7. 3. Wait about 1 to 3 minutes until the power turns on and the screen displays normally.
  8. Unplug the HDMI cable connecting the set-top box and the TV, then plug it back in securely.
  9. Ensure the internet (LAN) cable is properly plugged into the set-top box.
  10. If messages such as "Network Error," "No Signal," or "Authentication Failed" appear on your TV screen, it is usually caused by a set-top box signal issue or a poor cable connection rather than a TV malfunction. First, try turning the set-top box off and on again. If the issue persists, contact your set-top box service provider to request a signal check.

Why This Can Happen

Symptoms can have more than one cause, and the correct steps depend on the exact model, installation and operating conditions. Use the checks above to narrow the issue before service.

Safety and Model-Specific Guidance

Stop troubleshooting if you notice burning, electrical damage, unsafe heat, gas odor, refrigerant concerns, or water near electrical components. Follow the official LG USA instructions for your exact model.

Frequently Asked Questions

What should I check first for [LG Projector] An error message or "No Signal" message appears on the set-top box?

Temporary set-top box error: The set-top box system may become unstable due to prolonged use.

When should I stop troubleshooting and contact LG?

Stop if the product shows signs of electrical damage, burning, leaking near electrical components, or if the recommended checks do not resolve the issue. Use LG USA support for model-specific service guidance.

Does this guidance apply to every LG model?

Not always. Controls, error codes and service steps can differ by model. Confirm the exact model number and follow the linked LG USA article for model-specific instructions.

Related LG Products

These model pages are linked because the stored category or exact model matches this Help Library topic.

Buying Guides for This Product Type

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Read the Official LG Guide