Hi Folks,
Troubleshooting a TV that doesn't have backlight (Flashlight tests ok - I am getting data on screen - no backlight)
I see Firmware ICs and PS repair kits on eBay in addition to the obvious bad Backlight.
I'd hate to open up the panel to find a different problem though.
So here are some measurements I was hoping someone can tell if it's backlight or something else.
Main board is getting 13V standby and does generate the 3.3 PWR_ON signal
On the Power supply board:
D+, D- = 417 V
S+, S- = 402 V
(guessing if D+ and D- are same voltage then there is no current flow = translate to open LEDs?)
Readings above are when TV is on, and referenced to COM (Chassis)
I tested the problematic Diode - it has 417 V across it. Upon removal, it has 0.7k ohm, and 3.9 k ohm (keeps going up)
Any other measurements to take to confirm the diagnosis?
When I apply voltage from D+ to S-, and S+ to D- I get some LEDs lighting up. I don't have the panel open, so I don't know how many if any are dead LEDs.
Thank you
Thank you all
Troubleshooting a TV that doesn't have backlight (Flashlight tests ok - I am getting data on screen - no backlight)
I see Firmware ICs and PS repair kits on eBay in addition to the obvious bad Backlight.
I'd hate to open up the panel to find a different problem though.
So here are some measurements I was hoping someone can tell if it's backlight or something else.
Main board is getting 13V standby and does generate the 3.3 PWR_ON signal
On the Power supply board:
D+, D- = 417 V
S+, S- = 402 V
(guessing if D+ and D- are same voltage then there is no current flow = translate to open LEDs?)
Readings above are when TV is on, and referenced to COM (Chassis)
I tested the problematic Diode - it has 417 V across it. Upon removal, it has 0.7k ohm, and 3.9 k ohm (keeps going up)
Any other measurements to take to confirm the diagnosis?
When I apply voltage from D+ to S-, and S+ to D- I get some LEDs lighting up. I don't have the panel open, so I don't know how many if any are dead LEDs.
Thank you
Thank you all
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