HP LT1940-screen fades out (shuts off)

Ok, i got yet another hardware to repair, or at least attempt.
well actually two, other monitor i'm repairing has flikcering screen, only backlight flickers, nothing else shows up. i opened it and found some wasted electrolytics. so far, no big problems with that one....but This HP model, is bit another story:
It seems to power-up somehow, but after short period, couple seconds, screen turns off by itself.
i checked caps, no pulgs or other mechanical damage, checked them with esr meter, seems ok results. There is strange noise at startup, coming from one of transformers, i dont think its mains hum, sounds bit higher freguency. And when i turn screen on, backlight comes alive for some time, makes bit of noise like arcing or something, hard to describe. Is there other common faults with monitors than bad caps, and what i should check now?. i can take photos and service manual IS available in hand.

thanks for any help

Typical problems are the tubes, the inverter transformers, small blue HV capacitors, or poor connections.

If you google the datasheet for the inverter chips you may be able to figure out how to disable the auto-shutdown that prevents you working on it.

Thanks for reply, are those blue hv caps ceramic ones, like others found in SMPS systems? and is there any downside for disabling auto-off, like making more damage, as there is something that initiates the shut-off, right?. i try to google those chips, maybe it helps, as you suggested .

ok, i think i found the chip you were talking about, this is at the main power board, and if i got this right, if i tie adj (1) pin to gnd (4) pin, it should not shut down the system? or should i first check PWM with 'scope first, just to make sure it does what i think it does?

https://pdf1.alldatasheet.net/datasheet-pdf/view/84612/ONSEMI/NCP1200AP40G.html

hmm, i wonder did i mis-informed about situtaion: only screen shuts off, first it just dims, then fades completely, otherwise monitor stays on, power led doesn't turn to orange, it stays green

hey, little progress in this matter, i made some measurements with 'scope, from 1200AP40:s pin 5 (drive output) to see if if chip is faulty, seems not, but what do you think? sorry about image quality....scope settings are as follows:
10v/div, with 10x scope attenuation.
5ms/div horizontal
none change seen when fault occurs.

ref. point for scope was chassis of monitor, dont know was it the best place, but reliable.
i can take another shot if necessary