So when I got this TV it would turn on, as indicated by the orange light turning white, but I couldn't see a backlight turn on and I didn't see any image even when I shone a flashlight on it. After some research on badcaps I figured my best bet would be to test the voltage regulators. I'll try to get some better photos if anyone wants them, but for now these are the readings I got:
U5
L311
G1117
pin 1 = 1.37
pin 2 = 2.62
pin 3 = 5.00
U9
L311
G1117
pin 1 = 1.25
pin 2 = 2.49
pin 3 = 5.01
U7
L313
G1084
pin 1 = 2.04
pin 2 = 3.28
pin 3 =5.01
U4
L311
G1117
pin 1 = 2.04
pin 2 = 3.28
pin 3 = 5.04
U2
L311
G1117
pin 1 = 2.05
pin 2 = 3.28
pin 3 = 5.00
U8
L311
G1117
pin 1 = 0.00
pin 2 = 1.24
pin 3 = 3.24
U11
7805CT
RAL 930 G
pin 1 = 12.27
pin 2 = 0.00
pin 3 = 4.98
TUS2
EH13A
928K80
pin 1 = 0.00
pin 2 = 0.41
pin 3 = 0.06
Then I messed up when I tried to test the current going through the G1117 voltage regulators because the datasheet declared different dropout voltages at 800 mA (1.2 V) and at 1 A (1.3 V). So I think I accidentally crossed two pins when reading the 2nd pin on U8, because when I made contact the speakers let out some static noise. I backed off, then attempted it again and got a reading of about 1.1 amps. I then went on to read the current on the input and adjustment pins, just to see if there was any difference, and then I think I blew the fuse on my power board (it reads 0 V on one side of the fuse, and now none of the voltage regulators on the main board are receiving voltage).
I am going to try replacing this fuse and the voltage regulators at U2, U8, and U9, as these did not have output voltages within 2% of their expected values. Can I get some confirmation whether or not I'm diagnosing this right, and any sort of explanation of why I might have blown that fuse? Also are the U11 and TUS2 components voltage regulators as well? They looked like it to me, but I was unable to find any datasheets for them online when I searched.
U5
L311
G1117
pin 1 = 1.37
pin 2 = 2.62
pin 3 = 5.00
U9
L311
G1117
pin 1 = 1.25
pin 2 = 2.49
pin 3 = 5.01
U7
L313
G1084
pin 1 = 2.04
pin 2 = 3.28
pin 3 =5.01
U4
L311
G1117
pin 1 = 2.04
pin 2 = 3.28
pin 3 = 5.04
U2
L311
G1117
pin 1 = 2.05
pin 2 = 3.28
pin 3 = 5.00
U8
L311
G1117
pin 1 = 0.00
pin 2 = 1.24
pin 3 = 3.24
U11
7805CT
RAL 930 G
pin 1 = 12.27
pin 2 = 0.00
pin 3 = 4.98
TUS2
EH13A
928K80
pin 1 = 0.00
pin 2 = 0.41
pin 3 = 0.06
Then I messed up when I tried to test the current going through the G1117 voltage regulators because the datasheet declared different dropout voltages at 800 mA (1.2 V) and at 1 A (1.3 V). So I think I accidentally crossed two pins when reading the 2nd pin on U8, because when I made contact the speakers let out some static noise. I backed off, then attempted it again and got a reading of about 1.1 amps. I then went on to read the current on the input and adjustment pins, just to see if there was any difference, and then I think I blew the fuse on my power board (it reads 0 V on one side of the fuse, and now none of the voltage regulators on the main board are receiving voltage).
I am going to try replacing this fuse and the voltage regulators at U2, U8, and U9, as these did not have output voltages within 2% of their expected values. Can I get some confirmation whether or not I'm diagnosing this right, and any sort of explanation of why I might have blown that fuse? Also are the U11 and TUS2 components voltage regulators as well? They looked like it to me, but I was unable to find any datasheets for them online when I searched.
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