Magnavox 32md359b/f7 White Screen and with sound only

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Just to add this in playing around with these certain things before doing your test above, I turned tv on and seen a faint light grey box just within the perimeter of the TV it stayed for about 20 seconds the TV blinked and now it's back to the white screen

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Hmm. Maybe an OSD or menu or something? If the addressing voltages are wrong, it could cause a faint picture, I suppose...

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I don't visibly see a c201 c202, I see a CN201 but it is the flat flex we tested earlier, I am checking for Q201

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

They are on the inverter board I believe. They may not necessarily be there, there could simply be a space for them.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

found Q201, but on power supply side,,,,I see C203, 205 etc.. but not C201 or 202..going to look again

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Measured Voltage at Q201 it is double again at 50.7v, I am going to get my neighbors volt meter to double check, but both my meters can't be wrong lol...all the voltage spots through out the house, appliances, batteries, cable boxes are all correctly reading

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Very odd, how are you measuring voltage, can you show a pic of your meter with it in the normal measurement setting, also try repeating the measurement on the 500, 600 or 1000V range.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I'm using the 300 and 200 readings on right side of my meter

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Well by all means that should work although it wouldn't surprise me if the 300V and 200V are somehow sharing components (part of a voltage divider ladder - it's complicated...) But you get the same results with a different meter?

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I do get same result, not finding C201-202.....

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

Hmm. Anything on the bottom of the inverter? They might be there... in which case, an alternate probing location would need to be established.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I'm checking now, went over entire board, Thanks tom

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

tom not able to find C201 or C202........???

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

not on bottom of inverter

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

OK, different approach.

There's a connector CN1001 on the inverter. Near the high voltage mains side.

It should have on each of the pins (from the top, relative to chassis):

0V
15.8V
15.8V
0V (VGH)
0V
3.4V
3.4V
-6.2V
0V
0V (VCOM)
0V

Apparently VGH and VCOM for the LCD are both 0V. I don't believe this, as usually VGH is something like 12-15V, and VCOM is 25V for an LCD screen. So I wouldn't be surprised to see different voltages there. But if there's anything obviously missing, then that could be the cause of the white picture (all pixels letting light through - typically the "no power" state for many LCDs.)

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

ok on first five they read
0v
14v
0v
6.2v
0v
0v
I stopped there because it seems off from yours

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

I also believe there is about 15pins

[tom66]

Re: Magnavox 32md359b/f7 White Screen and with sound only

That may be CN1003... CN1001 is another connector, it goes to the LCD.

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

The CN1003 is the one that is smaller and toward bottom where the lcd is, the CN1001 has a flat flex that goes from power board to inverter board

[YEROC37]

Re: Magnavox 32md359b/f7 White Screen and with sound only

In which case the CN1003 is not producing any power what so ever...