Toshiba 40BV700B won't turn on.

[randomizer2]

OK so this TV cut out on me last week whilst playing my PS3 and has not came back on since. The standby light is on and the capacitive buttons still beep when pressed. I initially thought it was a faulty cap which I replaced. As this didn't make a difference I then replaced the entire power supply with one I found cheap on eBay which unfortunately also did nothing.

Any ideas what is causing this problem ?

Thanks

[randomizer2]

Re: Toshiba 40BV700B won't turn on.

OK now this is extremely odd. I put some headphones into the jack to check if the sound was coming through and it was just the speakers and screen that aren't working. Surprisingly there was sound but not normal TV sound. The sound of thumping bass and the strangest part the thumping is in rhythm with the red flashing light of SPDIF Optical out. So an issue with the sound perhaps? Or the main board in general?

[sordids999]

Re: Toshiba 40BV700B won't turn on.

Hello
removing the back and taking some pictures of the boards might help you further in fixing your tv

[tom66]

Re: Toshiba 40BV700B won't turn on.

Due to the very high failure rate of these PSUs and the fact that most sellers don't test their boards I think it's worth checking both PSU and main board. Main board failure is rarer on these models, although some do have audio faults.

[randomizer2]

Re: Toshiba 40BV700B won't turn on.

I'm fairly certain its a sound issue with the main board due to the sound from the headphone jack and the optical out clicking and flashing. Are sound problems fixable or does the whole board need replaced?

I doubt that two PSU would be experiencing similar faults and the buyer assured me they tested it before shipping.

[tom66]

Re: Toshiba 40BV700B won't turn on.

What I mean by audio problems is the TV works but there's no audio. It's fixable but requires good soldering skills, requires replacement of an audio amplifier IC. I doubt your TV has this issue -- it's just a symptom of another problem.

[randomizer2]

Re: Toshiba 40BV700B won't turn on.

I'm looking to replace the main board and was wondering if any vestel 17mb38-1 will work or do I need one for my specific model? I assume the latter for firmware and stuff but just double checking as I've seen cheaper ones for different TV's.

[vinceroger69]

Re: Toshiba 40BV700B won't turn on.

was you using hdmi when this happened? just read another post nearly same symptoms
try a factory reset Menu 4725 brings up the menu

[randomizer2]

Re: Toshiba 40BV700B won't turn on.

I was using HDMI on my PS3 at the time. I can't access the service menu as the TV won't even turn on, it's stuck in permanant standby.

[vinceroger69]

Re: Toshiba 40BV700B won't turn on.

I was using HDMI on my PS3 at the time. I can't access the service menu as the TV won't even turn on, it's stuck in permanant standby.

sorry my fault for not reading the whole thread .

[mark_maher]

Re: Toshiba 40BV700B won't turn on.

I just repaired a Toshiba 40BV700B with the exact same fault as you described. The main board was faulty - and had a short circuit on the 3.3V and 1.8V rails - which I traced to the HDMI switch IC (U133).
I've had a few occasions where HDMI switch IC's have failed.. Though, not as often as plain old bad caps on power supplies.....

[collings]

Re: Toshiba 40BV700B won't turn on.

I'm getting a similar problem, same model TV, however, there is a power light, no screen, no sound, but you do just about see a dim flicker on the screen. I cannot see any menus and cannot do anything with the TV.

Any ideas?