bush LCD32TV005HD help

[gobby009]

symptoms: turn tv on and the picture gradually goes brighter and brighter,open tv menu and the menu picture is fine.


diagnosis: opened tv and found the cable connected to the mainboard from the inverter had 2 totally burnt out loose cables as pictured in picture 1 below.connected a new inverter cable but problem still exists.not sure how long those cables burnt loose.could the burnt loose wires have damaged the inverter?looked at the power supply and spotted 1 bulging capacitor in picture 2 below.what are the chances of this capacitor being the problem?

any help would be appreciated.

[selldoor]

Re: bush LCD32TV005HD help

That capacitor is bulging change it for a good quality Panasonic FR or FM
Chances are caps of a similar brand/series will also be going bad.
Maybe also capacitors on the inverter - really need pictures of whole boards

[gobby009]

Re: bush LCD32TV005HD help

hi thanks for the reply cant see any other bulging caps and dont have a meter with capacitor readings on it.but here are a few pictures of the boards.

[selldoor]

Re: bush LCD32TV005HD help

OK well the nichicon caps on the inverter board should be ok I guess all you can do is to
change the known bad one and see if it helps. Check the pins are clean in the socket where the wire burnt and that they are well soldered to the board ( we have seen sometimes where pins have just been sat loose in the board!! )
Run it on test and check how hot the wires get. Finally give it a good dust down ( with the power off helps keep it cool though if its as cold as it is here that should not be a problem )

[gobby009]

Re: bush LCD32TV005HD help

do you think that 1 bad cap could be the cause of the problem?????

[selldoor]

Re: bush LCD32TV005HD help

Not a clue - is the cap next to the where the fault was - what value is the cap more likely the plug was not inserted fully into the socket or the cable could have been faulty - I cant see what voltage it was carrying or on how many wires sometimes if the current is high they have 3 or 4 wires carrying 12v or 24v. Is the Dimming control wire in the same cable
trace it back/forward and see what components might have been damaged if the dim was shorted to the 12/24v. May be voltage regulator?

[budm]

Re: bush LCD32TV005HD help

Cables burnt like that are due to poor contact between the header and female socket, it has contact resistance which will heat up and burn. There is only one connector on the inverter board, that cable should go to the power supply board which supplies 24V at about 5A of current, I do not thing the cable will go the the main board. I cannot tell since we do not have the pictures of the whole back side of the TV.

[gobby009]

Re: bush LCD32TV005HD help

the cable from the inverter board goes to the main board not the power supply and i replaced the burnt out cable but the problem still occurs.

[gobby009]

Re: bush LCD32TV005HD help

gonna replace that cap on the power board see if it is the culprit

[gobby009]

Re: bush LCD32TV005HD help

just noticed this ribbon cable that connects the tcon board to the screen and its looking a bit faded could this be part of my problem?

[selldoor]

Re: bush LCD32TV005HD help

I would not have thought so you can try removing and cleaning and test it for shorts/open

If replacing the cap doesnt help post good clear pictures of the sockets at each end of the burnt cable.

[gobby009]

Re: bush LCD32TV005HD help

checked the sockets the burnt cable came out of and they look fine no corrosion,no scorch marks and theres no movement in them on the board.

[gobby009]

Re: bush LCD32TV005HD help

ok so replaced the bad cap on the power supply abd the problem is still there here are some pictures of the fault.

[gobby009]

Re: bush LCD32TV005HD help

selldoor i see your in the uk.do you repair tvs? just wondering if i could send you the tcon board to fit a new as15-f chip on it as i dont posess the soldering skills required.think the chips only cost a couple of pounds on ebay.or if anyone else from the uk could do it.

[selldoor]

Re: bush LCD32TV005HD help

Sorry - no can do - I dont have the equipment or the skill/eyesight.