Re: LG 24MP55HQ no power on

Hi!!
need a circuit diagram.
backlight problem, when a signal is input, the lower half of the backlight goes out, on Q101 and Q102, the input voltage drops to 52V, and the output goes to 39v.
can anyone come across such a problem?
voltage at connector P102
1 -39.9V
2 -39.9V
5 -57.3V
6 -57.3V