This is another easy Vestel fix, worth checking if you have a dead TV with a vestel 17PW80 PSU.
I found zero virtually zero power going to the main board and the screen controller kept tripping.
I checked the capacitors for the usual bulges etc but they appeared to be fine.
There are 5x large diodes, just below the caps in the secondary section of the power supply. Soon found the fault:
Lift one of the legs on the first 3x – D708,D709 & D710.
Then check them with a meter – I found D710 to be shorted.
I soldered the other 2x back and tested the TV for 30 seconds with the shorted diode disconnected.
I would recommend replacing all three – you looking for a 200v 3A UF5402, easily available on ebay for a couple of quid.
Simple fix.
Perfect… Mine was D709
Thanks for the tip. Issue was on D710 on mine.
Thanks for this.
D709 was blown.
Replaced it with a UF5408 that I found in my junk box.
Thank you for the solution to my broken Toshiba. Exactly as described, one diode short circuited, I’ve changed all 3 at a cost of less than £2. It works perfectly.
That’s good – bargain repair!
Absolutely, can’t thank you enough for the guidance. I would probably never have found the problem, or at least spent hours tracing it. Big thanks and big respect.
Thank you so very much for your help, D710 was short circuit, so I will be replacing all three diodes with type UF5408. I used to be a CTV Engineer some 17 years ago and I left the trade before Flat Panel TV’s came in. But it was just like old times repairing SMPSU faults.
Thanks again,
Mike
Hi Mike,
Glad to hear that you got it sorted, cheers Rick.
Thanks for the info, However I have read elsewhere on the internet that these are 5A diodes not 3A. Is this info correct? I don’t want to buy the wrong ones.
Whoops missed that comment sorry! The ones fitted to mine where indeed 3A, regards.