2016 (65UH9500) Power Supply Testing Forcing on the Power Supply
When servicing an LCD TV and you need to Test the Power Supply, due to the symptoms the TV Won’t
Come On or
Read First Before Beginning the Power Supply Testing Procedure
TV Intermittent Powers Off, before beginning the Power Supply Testing READ THE BELOW FIRST.
Check the Front Power Indicator:
This may give some indication as to status of the power supply. If the Power LED is red, it indicates
Stand By voltage is Stand-available. When you press the Power button, does the Power LED slowly blink off.
This should indicate the TV is receiving the power on command and is responding.
Caveat: The Power LED can be turned off via the Customer’s Menu. If it has been sut off, then the Power
LED can’t be used for diagnosis.
The SMPS “Must” be producing Stand-By voltage when AC is applied. Examine the Voltage Label to see
what the voltage should be. In this TV, Stand-By is 7.8V and when the TV comes on, it jumps up to 18V.
Remember that the Main board and the Front IR/Joy Stick utilizes Stand-By voltage. They could be the
reason if Stand-By isn’t coming up.
TV Intermittent Powers Off: When the TV is turned on, bring up the “IN-START” Menu and go to the
Power On/Off History screen. The top (number 1) indicates the most recent reason the TV turned off.
Look for anything uncommon. Common entries are Off-By: Local_Key, Remote_Key, SW_Update (Not
normal in web-OS models).
Abnormal: Power_Off_By: AC_DET (indicates a loss of AC power).
You can look at almost any Training Manual from the last several years and
