It turns on long enough to see the logo/splash screen, and even the OSD for a second or two.
Voltages going from PS to Mainboard
Voltages going from PS to Mainboard
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Re: Magnavox 39MF412B, turns on for 10 secs then shuts off
first thing anyone is gonna ask for is photos of the back of the tv with the covers off and individual pics of each of the boards -
Re: Magnavox 39MF412B, turns on for 10 secs then shuts off
do you have a dmm?Comment
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Re: Magnavox 39MF412B, turns on for 10 secs then shuts off
Sorry, I spaced out, and forgot to paste.
Voltages going from PS to mainboard (with set OFF):
Now, readings with the set ONCode:Pin 1 Pin 2 0v Pin 3 6.9v Pin 4 0v Pin 5 0v Pin 6 3.3v Pin 7 18.2v Pin 8 0v Pin 9 6.9v Pin 10 0v Pin 11 0v Pin 12 6.9v
In particular, I'd like to focus on pin 7, which seems high when the TV is on. There are no other threads here on this model.Code:Pin 1 0v Pin 2 0v Pin 3 11.9v Pin 4 0v Pin 5 0v Pin 6 3.3v Pin 7 27.2v Pin 8 0v Pin 9 11.2v Pin 10 0v Pin 11 0v Pin 12 11.2v
Mainly, I want to document my findings. All caps appear good,
but it's probably worth replacing them all, retesting, just to see if there's a change.
Interesting bit of info: When the set sits for a while unplugged,
when plugged back in, the pin 7 readout is 18.2v, however once
the set turns on then off again, it drops to 25v, then back UP to 27.2v
and pretty much stays there with the TV off!
To me, this indicates a capacitor is storing too much energy and keeps
it after the set is off again. Does anyone concur?
I think this is the SM: http://elektrotanya.com/?q=showresul...oria=&kat2=all
I'll go over it in the morning and see if I find any good schematics to help with troubleshooting components.Attached FilesComment
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Re: Magnavox 39MF412B, turns on for 10 secs then shuts off
Yeah, I read it this morning and it was a manual for a CRT TV.
For some reason that's only result that came up when searching for Magnavox A21T0UH
Does any one have the correct manual for Magnavox chassis A21T0UH?
Or know of a good source for Philips / Magnavox service manuals?Comment
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Hi, I bought 6420 XFR that tries to boot but shuts down after about 3 seconds, CPU gets warm, fan starts.
So far I have tested all rails wich are good, BIOS flashed with CH341, 3.3,5, main rail present. multiple ram sticks tested. Sometimes it might stay on for longer like 4-5 seconds but not always, theres no picture whatsoever. Also on some rare occasions the caps lock flashes 1 time by itself.
NOTE: I am using bench power supply not dell charger with ID pin and NO battery present, kinda doubtful this would cause this issue.
Any help is welcome. Thanks !07-29-2025, 03:53 PM -
Hello everyone,
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CPU: Intel Core i5-11400H
GPU: NVIDIA GeForce GTX 1650
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Seems like we are dealing with a case of a corrupted BIOS after Intel Driver software attempted to flash the bios (haven't seen that before). The customer reported seeing a BIOS message while the screen was flickering during the Intel Display Driver installation. This was while the BIOS WRITE lock jumper was in place. Resulting in Loop restarting.
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Under the thermal cam, I can see that the CPU is initiating a heat signature for a second...
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