Transistor Replacement K4112 => K3596

[neilc6]

Re: Transistor Replacement K4112 => K3596

Maybe the discoloration is a red herring since that area generates a lot of heat and research indicates a bad CCFL bulb could also cause the backlight to shut off. Though, the burning smell indicates something is fried. The electrolytic caps are all Rubycon.

[neilc6]

Re: Transistor Replacement K4112 => K3596

I plugged the power supply board back in to measure the voltage on the CNE1 connector but the backlight stayed on and it's working again. But you know what they say about problems that go away by themselves....

[neilc6]

Re: Transistor Replacement K4112 => K3596

Ok, I found the real problem after looking at it again. Investigating the wire were it was scorched, the insulation had melted away where it contacted the tape they used to bundle the wires together and to tape it to the back of the panel. Shorts were probably causing the backlight to turn off. The burning smell was melting insulation.

[sparks2112]

Re: Transistor Replacement K4112 => K3596

Hi got same board as in pics. For a evotel tv. And wanting know what it says on NTC1 its a power thermistor or ceramic cap. Mine blown to pieces so cant see what it says onit. Any help much appreciated. Thanks

[budm]

Re: Transistor Replacement K4112 => K3596

It is the inrush current limiter, hopefully someone has the board to get the Value.

[sparks2112]

Re: Transistor Replacement K4112 => K3596

thanks for that bud. keep checking to see if any one had anything on this. but no joy.can buy these off rs components but 19 to choose from. could you recommend any? common ones etc. read a few threads you've been on about low ohms.diameter.watts etc. and mine was I think 13mm dia. but was badly blown and lost part now. seen a few 15mm.on there which would be ok. also some say application is for soft startmotor&switching power supply. some just for switching. and some for protection. which one would mine be for as could help narrow it down. for price of £1+ ill try a couple if they blow or cause more damage its all good was free tv so try anything lol. http://uk.rs-online.com/web/c/passiv...696D6974657226

[budm]

Re: Transistor Replacement K4112 => K3596

I would recommend 5 Ohms 15mm DIA.

[sparks2112]

Re: Transistor Replacement K4112 => K3596

closed till Monday. but will try it,and let you know how I get on.
thanks pal

[budm]

Re: Transistor Replacement K4112 => K3596

Once you install it, then you should check the ACV between the two legs after the TV is on for about 5~10 minutes to see what you get, the resistance of the NTC should go down when it get current flowing through it as it warms up.