Toshiba 40l1333b (SSL400_05DA) - backlight problem

Thread Starter

oldmazda

Joined May 18, 2020
11
I have the problem with backlights as only half come on and the voltage showing is 62v to the led strips. I have tried to get the links showing in the thread here https://forum.allaboutcircuits.com/threads/toshiba-40l1333b-ssl400_05da-backlight-problem.153775/ But keeps coming up with error messsage, I feel if i had the viltages infomation which will be in these links i stand a chanceif i knew the output voltages on the components so i can check if any are faulty , So if anyone has the info on this driver board same as in picture, i would appreciate the help.Thankyou for reading thisscreen-04.29.02[31.01.2020].png
 

R!f@@

Joined Apr 2, 2009
9,734
That older link is working.
That OP did not have a driver issue.
His issue was bad LED strip interconnects.

U can even check the LED strips separately. But you need to dismantle the whole LCD assembly.
 

Thread Starter

oldmazda

Joined May 18, 2020
11
Welcome to AAC.

Before that, are you sure the LED strip does not have broken LED/s?
I have checked for continuity in the green strip the led strips connect to and also all led`s all ok when i checked voltage from the driver board to the green led strip it is only 62 v and feel it should be more, So i feel something wrong on the driver board.As when plugged in only half of them light up thnx
 

Thread Starter

oldmazda

Joined May 18, 2020
11
That older link is working.
That OP did not have a driver issue.
His issue was bad LED strip interconnects.

U can even check the LED strips separately. But you need to dismantle the whole LCD assembly.
The link i put on does work but the links that was put on that link don`t as follows.
Here is a number of photos with varying test results
-----------------------------------------------------------
correct voltages on SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.png

results of testing original SSL400_05DA (from the tv)
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.original board - test results.png

results of testing replacement SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.replacement board - test results.png

results of testing SN358, TR10E and CN001 - original SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/original - ic results.png

results of testing SN358, TR10E and CN001 - replacement SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/replacement - ic results.png


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R!f@@

Joined Apr 2, 2009
9,734
The link i put on does work but the links that was put on that link don`t as follows.
Here is a number of photos with varying test results
-----------------------------------------------------------
correct voltages on SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.png

results of testing original SSL400_05DA (from the tv)
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.original board - test results.png

results of testing replacement SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/151120-IMG_20151120_221823.v2-1.black text.replacement board - test results.png

results of testing SN358, TR10E and CN001 - original SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/original - ic results.png

results of testing SN358, TR10E and CN001 - replacement SSL400_05DA
http://testing.dfear.co.uk/toshiba_40l1333b/replacement - ic results.png


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Ur links are down.
 

R!f@@

Joined Apr 2, 2009
9,734
Look at the green PCB strip and check if all the LED strips are connected in parallel or in series parallel combination
 

R!f@@

Joined Apr 2, 2009
9,734
You can check the LED's one by one with a good DMM in diode check mode.
I always do that to identify dead LED's. Then I just replace them with exact replacement no.
 

Thread Starter

oldmazda

Joined May 18, 2020
11
All the strips are in correct position. What i will do is check em 1 at a time and correct any not working and also redo all connections and check a strip at a time with 24v also check the continuance on green strip .Then come back on here with results. The question i have now is (A).How can i get them links up and what is the voltage the driver board should show to the green strip when powered up . I would love to see these links Thanx
 

R!f@@

Joined Apr 2, 2009
9,734
Do not apply voltage to things you have no idea about.
U will probably blow the LED's.
60V is nominal for those strips but they are distributed and current limited.

Just check the LED's of the dead strips one by one. Use a 5V source with series 330Ω or 470Ω resistor to check each LED separately.
I use my CC PSU to test each strip separately and then check the LED with DMM.

You apply power to those LED's without current limit, you will blow them.
 
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