M # CM 870, at turn on Compaq logo appears for a second, then no display. Place a light onto the screen, you can see the info from the computer. How can the lcd, or lamps be bad, if display comes in for a second perfectly? Dani.
The inverter is going into a protect shutdown after the initial attempt to turn on the lamps. Odds are very good that the inverter has a set of output devices and transformer for each lamp, but only one driver ic. If there is a problem in any of the output stages the driver ic shuts down which turns off all the lamps.
I have found many that used the round surface mount electrolytic capacitors go bad cause this, a bad tube also cause this, along with simple open surface mount fuses that appeared to open for no reason.
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