When your TV has a black screen even when it's on, it's quite possible it could actually be your external device and not your TV. If your TV is connected using a One Connect Box, there are a couple of extra steps to troubleshoot.
- Tv without the one connect box has no picture
·Press the Home (Menu) button on the remote.
- If the menu appears, the TV is powered on but is either not on the correct source or not receiving a signal.
- If the menu does not appear, the TV may be having power issues.
Confirm the TV is set to the same source as the external device.
- For instance, if your cable box is connected to HDMI 1, set the TV source to HDMI 1.
- If the TV is set to the correct source, but there is still no image, unplug and reconnect the AV connections one cable at a time, from both ends of each cable. If there's any damage to the cable, it will need to be replaced.
Test the HDMI cable.
- To perform the test, make sure the TV's source is still on the HDMI setting for the cable you want to test, and then navigate to Settings > Support > Self Diagnosis > Signal Information > HDMI Cable Test > Start Test.
Test different external devices.
- The final thing to rule out is the external device you're using. Try connecting a different device, or using a different source port. If you were unable to test the cable in the previous step, then try swapping the cable, too.
- If the TV can display a picture in any other setup, then you've ruled the TV out as the cause of the issue. Keep trying various setups until you identify the device or cable that is not working, and troubleshoot or replace it.
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