Seems to be a backlight issue. I think there are two backlight bulbs in the 24" iMac LCD screen so the top one could be bad or the inverter board for this backlight. From what you describe the backlight try to power at boot up but only flash and doesn't light.
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Seems to be a backlight issue. I think there are two backlight bulbs in the 24" iMac LCD screen so the top one could be bad or the inverter board for the top backlight. From what you describe the backlight try to power at boot up but only flash and doesn't light.
Seems to be a backlight issue. I think there are two backlight bulbs in the 24" iMac LCD screen so the top one could be bad or the inverter board for this backlight. From what you describe the backlight try to power at boot up but only flash and doesn't light.