Technika LCD32-209X fault!

[netdent]

Hi guys looking for some advice with this one, plugs in the blue standy light lit seems to power up as in light goes out slight delay then blue light flashes rapidly? marrowed it down to psu as I had a working main board to try, have read some info where the 2 blue bead caps near the invertor transformer might be faulty? but none to try to hand, anyone had this fault before? psu is 17IPS10-3 vestel

thanks Ronnie

[budm]

Re: Technika LCD32-209X fault!

Those blue small caps are ballast caps for the lamps, you have o remove them and Ohm them out, they should show open circuit. They are low value around 10~20pF at about 8~10KV rating. You should Ohm out the 4 surface mounted MOSFET's on the bottom of the board (bottom right of your second pictures) to make sure they are not shorted out.
From the look of your pictures, I do not see any caps with domed tops but that does not mean they are good, bad caps can look normal but can have high ESR or reduced values.

http://s807.photobucket.com/albums/yy352/budm/

Did you do any voltage checking at all yet?

[netdent]

Re: Technika LCD32-209X fault!

Those blue small caps are ballast caps for the lamps, you have o remove them and Ohm them out, they should show open circuit. They are low value around 10~20pF at about 8~10KV rating. You should Ohm out the 4 surface mounted MOSFET's on the bottom of the board (bottom right of your second pictures) to make sure they are not shorted out.
From the look of your pictures, I do not see any caps with domed tops but that does not mean they are good, bad caps can look normal but can have high ESR or reduced values.

http://s807.photobucket.com/albums/yy352/budm/

Did you do any voltage checking at all yet?

Hi thanks for the info, no not done any voltage checks and dont have an esr meter, will check those mosfet's, I did put my meter across thos 2 caps in situ, the were open on continuity setting not checked on high ohms

thanks Ronnie

[minimania]

Re: Technika LCD32-209X fault!

this psu is used in a 32" alba tv too
i repaired 17 months ago
fault was sound but no pic (was the 2 caps (5pf 3kv) replaced both and set worked fine)
its now come back with same fault

[greenhoughpeter]

Re: Technika LCD32-209X fault!

Hi guys looking for some advice with this one, plugs in the blue standy light lit seems to power up as in light goes out slight delay then blue light flashes rapidly? marrowed it down to psu as I had a working main board to try, have read some info where the 2 blue bead caps near the invertor transformer might be faulty? but none to try to hand, anyone had this fault before? psu is 17IPS10-3 vestel

thanks Ronnie

Hi Ronnie, I was reliably informed that this is indeed a capacitor failure on the power board so I picked up a refurbished pw26-4 board up from www.tvpartsuk.co.uk for £15:99 and it did the trick......saved me from using my less than pracgive a first class service and know what they're doing. tised soldering skilks...those guys