My guess is that the fan(s) on your TV have a speed sensor. It is possible that the new firmware changed a setting on the main control pc to start monitoring the fan speed. Your PC most likly has the same type of fans such as on the main CPU. Most PC motherboards now have the ability to monitor that fan and will turn off the PC if the fan fails.
This sounds like what is happing to your TV. The firmware may have started monitoring a fan that it didn't before, or, changed the speed at which it would detect a failure. On a PC, most motherboards allow you to change the fan speed monitoring and even turn it off. This is to allow system builders some flexibility in the fans they use in the system (or even use fans with no speed sensing capability).
Your TV, unlike a PC is a pre-built unit. The TV is sensing a failure in one of the fans on the unit and is shutting down to prevent further damage. Just because you can here a fan does not mean that it is "Fan 1". It could be another fan you are hearing. Or, you could be hearing Fan 1, but it is spinning slower then it should.
It is possible that there is a service menu that allows the monitoring of the fans, and there might even be a way to disable or change warning levels. But, I wouldn't even try. Going into the service menu is a very quick way to void any warranty on your TV.
The TV is shutting off to prevent any further damage to the TV in case one of the cooling fans has failed. Hopefully, the TV is still under warranty as it sounds like something is, or has failed in the TV.
As far as it happening after a firmware upgrade, as long as the firmware you installed was made for your TV in your country (exact SIZE, model, sub-version, etc), it is most likely a coincidence. But, it could also be possible that it is something Samsung added that was missing in a earlier version.
One thing I would do is make sure that you downloaded the correct firmware. If not, make sure you get the correct firmware loaded! Make sure there is not a different firmware for different size TV's as well. A larger TV could have additional fans. Otherwise, I would give Samsung service a call.
Sorry!
Hi
I updated the LCD TV LA40A680 to a new firmware and now I get a message Check Fan 1. The TV shuts off after several minutes. I'm sure I can here a fan running. Is there a way to tell the TV to ignore the fan message?
Any ideas?
Thanks

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