Agilent E8357A LCD backlight died or toggled CCFL OFF ??

[EE-digger]

A month ago I was testing external monitors as a possible upgrade for the internal LCD.  I found a nice 10" 800x600 module with VGA input that gives an absolutely stunning display.  Not an MS fan but have to thank windows for nicely supporting the display options.

For various reasons, I decided to stick with the internal display.  The Lynx 3D video controller is fussy but can be tamed.  The LCD remained dark until I realized the display was actually ON but backlight was off.  Confirmed with a bright desk lamp.  The Lynx hot keys work so I can toggle external VGA, LCD or both.

Does anyone know of control bits for the backlight that may have been accidentally toggled.  I had NO display problems before my external tests.  I can't believe it randomly died exactly when I needed to use it again ... after a few weeks of laying idle.

I've been through the programming guide but found nothing backlight related.

[tautech]

I can't believe it randomly died exactly when I needed to use it again ... after a few weeks of laying idle.

Yeah that seems strange but random things do happen.
Maybe check there is some inverter activity in the backlight circuitry.
These things are normally noisy so a near field probe might be good enough.

[EE-digger]

I found a tech bulletin on a commonly failing fuse on the inverter PCB in this series.  It was covered for replacement for years but that ended.  I'll be checking that first. 

[EE-digger]

For future reference, it was just the fuse on the inverter board.  It's a 2A SMT, possibly 0805.  Our Agilent guru, CV, seems to recall that it should have been 3A or 4A, the latter of which I happened to have on hand.

We have glitchy power outages from fallen trees around here and when the interrupter cuts power to the neighborhood, it's BANG, BANG, BANG.  Not surprised there may be some power up surges.