LG 2015 (EF Series) OLED SMPS Schematic

2015 (EF Series) OLED SMPS Testing Forcing on the Power Supply

Testing the Power Supply

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65EF9500

Updated 03-16-2016 ver2

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Read First Before Beginning the Power Supply Testing Procedure

When servicing an OLED TV and you need to Test the Power Supply, due to the symptoms the TV Won’t Come On or

TV Intermittent Powers Off, before beginning the Power Supply Testing READ THE BELOW FIRST.

Check the Front Power Indicator:

Take note of the front Power LED. If it begins to “Blink” (about once a second) continually for 30 seconds and the TV makes no attempt to turn on, it means that the Main board is “Latched” and no functions work.

If this happens, the Main board will not function again normally until it is unlatched even if the Main board is placed in another identical OLED model.

To Unlatch the Main Board:

Press the “Power Only” button using the Service Remote. This will place the TV into P-Only mode. P-Only = TV comes on in Full White Raster. A P-Only black box with text appears in the upper left hand side of the screen. P-Only mode will also bypass the “Burn_Det” circuit, which will allow the TV to turn on normally.

If the TV Comes on Normally in P-Only Mode:

Press Exit on any remote and the screen is not full white raster. Press the “In-Start” button and enter the Service

Menu. Scroll down to “Power_Off_History” and look at the events that shut off the TV. If you find three consecutive

“INV_ERROR” this indicates activation of the Burn_Det circuit which is what “Latched” the Main board. If this is the case, look for the Service Bulletin for this model; “Improved Auto Power Off / No Power issue”. This bulletin requires you to update the Software via USB only.

If the TV Still Won’t Come On:

In this case follow the Power Supply Testing, check the Main board. If both are OK, replace the Panel.

If the OLED TV Shuts Off Intermittently:

With the OLED turned on, press the “In-Start” button and enter the Service Menu. Scroll down to “Power_Off_History” and look at the events that shut the TV off. If you find “PWR_OFF_by_20V_DET or PWR_OFF_by_INV_ERROR”, look for the Service Bulletin for this model; “Improved Auto Power Off / No Power issue”. This bulletin requires you to update the Software via USB only.

If the TV Still Continues to Intermittently Shut Off:

In this case follow the Power Supply Testing, check the Main board. If both are OK, replace the Panel.

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