Assuming the blank screen is black (blank could mean illuminated but with no image) and the power indicator shows operating mode, then a backlight fault is a safe assumption.
You'd need to open the monitor case and see if you can identify a cause, some people are comfortable doing this, others not.
A faulty CCFL lamp is possible but uncommon. Much more common is a fault in the backlight inverter or PSU. Common causes are bad electrolytic capacitors (often they bulge, split or leak fluid), or there can be bad solder joints on inverter components like transformers or transistors.
Edited by Platypus, 07 February 2011 - 05:46 PM.