I think i killed it Toshiba 40L1333DB

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Makes sense to do this, specially since there seems to be a question of the quality of some of the backlights being sold to begin with.

[angelos]

Re: I think i killed it Toshiba 40L1333DB

Replacing individual LED's has a 30 to 40% success rate for a telly lasting 6 months longer. I have been totally discouraged from repairing them. The way to go is repla cing them but that is too costly.
I thought of getting a hot plate, those temperature controlled units of which you can program a "heating profile" and then replacing all LED's but the issue is aligning the lense caps whilst moving the diffuser over it to ensure you don't have a round bright patch on screen. That's a real pain. I use epoxy which takes 10 minutes to harden. Imagine doing that 60 times over. I rather commit suicide.
Is there any better ideas?

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Replacing individual LED's has a 30 to 40% success rate for a telly lasting 6 months longer. I have been totally discouraged from repairing them. The way to go is repla cing them but that is too costly.
I thought of getting a hot plate, those temperature controlled units of which you can program a "heating profile" and then replacing all LED's but the issue is aligning the lense caps whilst moving the diffuser over it to ensure you don't have a round bright patch on screen. That's a real pain. I use epoxy which takes 10 minutes to harden. Imagine doing that 60 times over. I rather commit suicide.
Is there any better ideas?

i must admit i thought i had made a pretty nice job of repairing the led strips and the repaired leds still work but others have now blown that were previously ok. for £25 i dont think a full new set is too bad even if they are from china and take a couple of weeks to arrive but my question is.... is it worth the effort or am i still going to face problems even after installing new led strips.

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Conversation here: https://www.badcaps.net/forum/showth...ight=40l1333db

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Another current modification, increased resistance by changing from 3.6 to 5.6 resistors, which lowers current to leds. https://www.youtube.com/watch?v=ogtfojsIZK8

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

they are all the original strips that i have repaired by piggy backing salvaged / working leds. and on 1 strip the connector had failed which i did a solder repair to. the the 'new' failed leds are different ones that had been fine when i tested each strip before rebuilding the screen.

Ok, oops, got you mixed up with another poster who was using new and old leds together.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

well my lovely new set of led strips arrived from china this morning, faster than i expected really.
tested each strip and all was fine. fitted strips to tv and powered up and hallelujah every led lit just fine. rebuilt the screen again and connected everything (double checked the connections). turned on and everything is working great, nice picture, sound everything but after 20 seconds the back-lights go off. tuned tv off and back on and everythings fine again but only for 10-20 seconds and now its the same each time its turned on, everything fine for a few seconds then back-lights off.
now in stumped again so any help would be greatly appreciated.

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Maybe try some of the reset methods.

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Some discussion here. https://forum.toshiba.eu/showthread....a-TV-26AV635DG

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Some discussion here. https://forum.toshiba.eu/showthread....a-TV-26AV635DG

good idea, tried that but still the same sadly.

what i have noticed is that when its cold / been turned off longer then the backlights stay on longer when first turned on and then shorter when its still warm. also i managed to get into the menu and turned that backlight level up to high (from low as it was) and that seems to shorten the time that the backlight works. im wondering if maybe it could be a bad connection on the new led strips so contemplating taking the screen to bits yet again to check if i can get the lights to come back on with a bit of a wobble of connectors. anyone think that seem possible or logical?

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

That seems to be a backlight symptom, when it "shortens the time" like you describe.

[alerton]

Re: I think i killed it Toshiba 40L1333DB

That seems to be a backlight symptom, when it "shortens the time" like you describe.

just got the screen in bits again and the led strips all seem fine. when first powered on theyre all lit bright and when they 'go off' again they actualy are all still lit just very dim and wobbling the connections to the strips does not help at all. so my theory of a bad connection seems to be wrong. so am i again looking at a power supply issue?

[Diah]

Re: I think i killed it Toshiba 40L1333DB

could you during the time it turn on log in service menu.. i am sure the old BL are different from the new. post photo of the first page

[alerton]

Re: I think i killed it Toshiba 40L1333DB

could you during the time it turn on log in service menu.. i am sure the old BL are different from the new. post photo of the first page

dont think thats going to be possible, it only stays on a maximum of 20 seconds and i dont know how to get to the service menu anyway sorry

[Diah]

Re: I think i killed it Toshiba 40L1333DB

dont think thats going to be possible, it only stays on a maximum of 20 seconds and i dont know how to get to the service menu anyway sorry

then use easy way, the Red Line of LED cut it at the middle and put 10K Ohm Resistor 2watt , you can this R value adjusted more or less till you have stable BL

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Ok, what next? unplug backlights from powerboard and see if you have expected voltage going from powerboard out towards backlights?

[nomoresonys]

Re: I think i killed it Toshiba 40L1333DB

Some testing here, different brand tv but gives the basics for testing. https://www.youtube.com/watch?v=uIrlbsbiltY

[alerton]

Re: I think i killed it Toshiba 40L1333DB

Ok, what next? unplug backlights from powerboard and see if you have expected voltage going from powerboard out towards backlights?

ok with the backlights disconnected:-

+ / ground is 121v constantly

-/ ground is 10.3v at switch on and drops to 1.8v after a few seconds

with the backlights connected:-

+ / ground is 121v constantly

-/ ground is 15v at switch on and drops to 13.2v after a few seconds

[alerton]

Re: I think i killed it Toshiba 40L1333DB

then use easy way, the Red Line of LED cut it at the middle and put 10K Ohm Resistor 2watt , you can this R value adjusted more or less till you have stable BL

once i find / fix the fault i might well do this to reduce the backlight and extend their lifespan but i really need to find the fault first. thanks for the tip

[Diah]

Re: I think i killed it Toshiba 40L1333DB

once i find / fix the fault i might well do this to reduce the backlight and extend their lifespan but i really need to find the fault first. thanks for the tip

i would like to explain some things about LED BL. its not Salad you can add what you like, either if you put whole new one doesn't mean you are succeed,

Chinese use all LED 2538 or 3030 for direct LED BL, the trick they used that then write for example your Toshiba. but they took only from Toshiba the Length of the strips, and the amount of the LED and the distances between them. and this they do for all brands as whole TV set LED BL. so its game of chance if the LED are same specification as the original. my way always refer to repair one by one only.

each TV on the PSU we have IC which control the BL and protect the set from over load. with out Manufacture data sheet we cant guess, specially with Toshiba vestel.

this we use the add R to by pass the protector circuit not to reduce the LED power. its matter of V fw. and current in use. when its go higher as designed PSU will cut them off.