Hi folks..
I got this Samsung UN55J620D (similar to the 55J6200,...)
Backlight dead - TV turns on, picture comes up (with flashlight)
So I have the backlight set on order. However, I was bored and I started repairing the strips. LEDs are standard 3 V, and I have tons of these.
Got them all done (many were bad) - put them in the TV.. testing checks out with the tester all the way from 5 mA to 220 mA..
With just power supply connected to LED strips.. I turn the TV On, and they start flashing almost 1Hz - then the weak unreplaced LEDs would blow, and I would replace .. so on. Now they're just flashing, nothing is failing.
so I unplugged the LED strip and I see pin 1 of the LED string reach ~320 V.. they slowly drop to about 275V, then back up to 320 V then slowly down.. so on.
I tested the large diodes on the power supply - seem to be fore the 13 V, and I get steady 12.9 V. The smaller diodes all tested (desolder one lead and check resistance both direction - one direction is about 6 M Ohm, and other direction is open (High Impedance)
I checked D9101 Voltage and its similar to M1+ (pin 1 of LED string)
R9161 reads about 0.4 Ohm, R9162 is 1.9 Ohm.
All the LEDs still check out (I will install the new set when I get it.. just want to make sure I don't have a PS problem as well)
Thanks in advance.
I got this Samsung UN55J620D (similar to the 55J6200,...)
Backlight dead - TV turns on, picture comes up (with flashlight)
So I have the backlight set on order. However, I was bored and I started repairing the strips. LEDs are standard 3 V, and I have tons of these.
Got them all done (many were bad) - put them in the TV.. testing checks out with the tester all the way from 5 mA to 220 mA..
With just power supply connected to LED strips.. I turn the TV On, and they start flashing almost 1Hz - then the weak unreplaced LEDs would blow, and I would replace .. so on. Now they're just flashing, nothing is failing.
so I unplugged the LED strip and I see pin 1 of the LED string reach ~320 V.. they slowly drop to about 275V, then back up to 320 V then slowly down.. so on.
I tested the large diodes on the power supply - seem to be fore the 13 V, and I get steady 12.9 V. The smaller diodes all tested (desolder one lead and check resistance both direction - one direction is about 6 M Ohm, and other direction is open (High Impedance)
I checked D9101 Voltage and its similar to M1+ (pin 1 of LED string)
R9161 reads about 0.4 Ohm, R9162 is 1.9 Ohm.
All the LEDs still check out (I will install the new set when I get it.. just want to make sure I don't have a PS problem as well)
Thanks in advance.
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