Need expert advice once again.
Been staring at this 710N whose backlight flickers about 10 times per second. Pretty annoying. It seems like setting brightness to 100 sets the duty cycle to 90% or so and at about brightness 20 the monitor just shuts off. It's like the inverter is getting a low PWM signal somewhere, can't figure out where.
- Tested with different backlight panel -> same issue
- installed new(ish) caps on the 15V and 5V bus
- 15V and 5V bus look good. 15V dips to 13V-14V when the CCFLs come on
- transformers check out - ~950ohm on the secondary
- inverter fet and transistor check out good
The only slightly strange thing I could find is the input bus is at 162 where it is normally 169VAC. It can't be that, though?
The only other thought I have is if it's those square capacitors by the transformers (names escape me right now). I'm too lazy to pull them out to test on my DVM's "CAP" setting... someone tell me if I should?
ADJ_BL from the logic board is ~0.535VDC. Not sure what it should be.
I can't find schematics for this inveter board. It is FSP035-2PI01. Other ideas?
Been staring at this 710N whose backlight flickers about 10 times per second. Pretty annoying. It seems like setting brightness to 100 sets the duty cycle to 90% or so and at about brightness 20 the monitor just shuts off. It's like the inverter is getting a low PWM signal somewhere, can't figure out where.
- Tested with different backlight panel -> same issue
- installed new(ish) caps on the 15V and 5V bus
- 15V and 5V bus look good. 15V dips to 13V-14V when the CCFLs come on
- transformers check out - ~950ohm on the secondary
- inverter fet and transistor check out good
The only slightly strange thing I could find is the input bus is at 162 where it is normally 169VAC. It can't be that, though?
The only other thought I have is if it's those square capacitors by the transformers (names escape me right now). I'm too lazy to pull them out to test on my DVM's "CAP" setting... someone tell me if I should?
ADJ_BL from the logic board is ~0.535VDC. Not sure what it should be.
I can't find schematics for this inveter board. It is FSP035-2PI01. Other ideas?
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