Dead Vestel 17IPS71 power board

[london-freddie]

Re: Dead Vestel 17IPS71 power board

Te5an
6300a
myc

[budm]

Re: Dead Vestel 17IPS71 power board

What is the P/N of the SMPS IC U202 in the primary side?

[london-freddie]

Re: Dead Vestel 17IPS71 power board

to the best of my knowledge and ability and after watching the video
diodes seem ok led mosfet seems ok and no voltage at Ir sensor

[ReeceyBurger123]

Re: Dead Vestel 17IPS71 power board

If the Led mosfet is good put your black probe on chassis ground and then see if you have 5v and 3.3v at the Ir sensor (pins 2 and 3 of the sensor) which is mounted on the front frame of the Tv, if so the Psu if fine and your motherboard has failed.

[ReeceyBurger123]

Re: Dead Vestel 17IPS71 power board

So the diodes with your meter in diode mode do not beep ? Also what about the Led mosfet
.

[london-freddie]

Re: Dead Vestel 17IPS71 power board

yes checked them all seem ok

[ReeceyBurger123]

Re: Dead Vestel 17IPS71 power board

+1 He needs to have some idea of process so a good suggestion.

Cheers, hopefully helps him out. Does save alot of time typing things up

[dick_barton]

Re: Dead Vestel 17IPS71 power board

Please watch my video, yes its a different Psu but same concept:

https://m.youtube.com/watch?v=owmBcJ91yJw

+1 He needs to have some idea of process so a good suggestion.

[budm]

Re: Dead Vestel 17IPS71 power board

no voltages at all at CN3/4 connector

May I ask what you use for GND ref. for your meter?

[ReeceyBurger123]

Re: Dead Vestel 17IPS71 power board

Please watch my video, yes its a different Psu but same concept:

https://m.youtube.com/watch?v=owmBcJ91yJw

[ReeceyBurger123]

Re: Dead Vestel 17IPS71 power board

Checked the output diodes for S/C ?

[london-freddie]

Re: Dead Vestel 17IPS71 power board

sorry but would not know where to start looking

[dick_barton]

Re: Dead Vestel 17IPS71 power board

I don't know how close this schematic is but it's time to start checking components.
There are a lot of 0 Ohm resistors that I would check as well.

[london-freddie]

Re: Dead Vestel 17IPS71 power board

no voltages at all at CN3/4 connector

[dick_barton]

Re: Dead Vestel 17IPS71 power board

Thanks. So you have rectified DC so now to find out why you have no DC outputs.
Could you measure the dc voltage on CN3-CN4 (black connector) with the mainboard disconnected and see if there is at least a standby voltage?

[london-freddie]

Re: Dead Vestel 17IPS71 power board

senior moment i think

[london-freddie]

Re: Dead Vestel 17IPS71 power board

ah 336V DC

[london-freddie]

Re: Dead Vestel 17IPS71 power board

am i doing this right ?

[dick_barton]

Re: Dead Vestel 17IPS71 power board

meter set at 600V AC red probe on +ve leg black probe on -ve leg 747 or 748v on all three caps if that makes any sense

DC Voltage measurement please.

[london-freddie]

Re: Dead Vestel 17IPS71 power board

meter set at 600V AC red probe on +ve leg black probe on -ve leg 747 or 748v on all three caps if that makes any sense