LCD show "Warning Power Supply 6D"??

If it's dual power supplies, probably one went down six days ago (unplugged?) . I would clear the LCD, and see if it comes back. If the power supply is bad - it will tell you. Also, you can look in the logs. Hard to say without being there.

how to clear LCD with LCD panel?

 

 

i don't know which between ...press x button 2 times OR press check button 1 times ?

When the error is displayed, I think you can acknowledge it using the check button (with the green tick).

You can also clear it remotely - http://support.f5.com/kb/en-us/solutions/public/11000/000/sol11094.html

thank you

 

 

i clear lcd error and warning message disappear and not come up again. and everything work fine

 

 

so i think cause by electric 2-phase and power failure , it make power supply up only 1 at first , then lcd show that warning message.

 

 

thank you ^_^