F5 Enterprise Manager 4000 Not Responding

Hi All,

I have got a Enterprise Manager 4000 which went offline couples of days back. On the LCD screen it says "Power Standby Mode. Press Enter to Command Power On". I have tried to press the green button but the F5 logo blinks once and goes dark again. I found a solution online that mentioned to hold the green check button on the LCD panel for a second to get the device out of stand by mode. Tried this as mentioned earlier but no joy. Also i am unable to get any response from the device on the serial port. All the other ports are not responding either. Has anyone came across this situation before ?

Thanks