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Vizio E370vl main bd #3637-0572-0150 power on problem.

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ramondo

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First post, Thanks to all.

History:Set operated nonstop for 3 years with bedridden aunt.
Set off but plugged in for 2 months.
I acquired set and it operated for about 30 mins then it was turned off.
The next restart gave amber logo, then white logo for a couple of secs, then back to amber, nopic no backlight.
Multiple attempts to restart gave same results.
After doing some googeling I figured the eeprom was the likely culprit (because of many similar posts). I ordered one online and installed it but now I have only amber logo. After more googleing I have come to the conclusion that Visiohas made a number of different boards for the same model.(should have done more googeling).

Now for the hard part.
I have found that the LG 32ld400 service manual has the same main board 0171-2271-3274(silkscreened), print and component
layout as my Visio but the Visio is not identically populated.(all items on visio board are on the LG schematic, however the Visio is missing all of the TCon parts, they are on a separate board). ALL fuses are good. I do have 5vsb from power supply board but no others. I have powered the main board from a bench 5v. supply, tested and confirmed the following voltages,3.3v,1.12v,1.80v,1.25v. I do not believe I have the proper PSON signal at pin 11(see pic). Mine goes from 450mv(millivolt) low to 478mv high consistently with every power on button push. After much head bashing I come here for your help.


Looking up datasheets for the Eproms I find many differences (all of which are way over my head)
Orig MX25L6445EM21-10G --- 104 mhz clock-64M-BIT [x 1/x 2/x 4] CMOS MXSMIO
Replacement MX25L6406EM21-12G --- 86 mhz clock-64M-BIT [x 1 / x 2] CMOS SERIAL FLASH
Question, I realize there are no guarantees, just your best idea of what you would do next.
Does the eeprom programming start after the PSON signal is sent to power supply board?
Am I in the right area by replacing the Eeprom with the orig type?
Will a bad (corrupt) Eeprom stop the PSON signal?
Do you think I will harm the main board supplying a PSON high to the power supply?




Why is it so hard for me to upload photo's,,, where is the attachment location??? (SOLVED)
After much searching,I found that unchecking flash based file uploader in Profile page Preferences allows image upload when your editing your post.. I am still not able to find the "Go Advanced" button..
 

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