Quick diagnostic question

I decided to do something about the dead backlight in my K5, but wanted to make sure the inverter wasn't dead also.  I never heard any high pitched whine from the inverter, but decided to see if there was any AC curent flowing.  I unplugged the green and violet leads from the board and when I turned it on, I immediately heard the very high pitched whistle coming fro the inverter.  When I touched the probes from my multimeter to the pins, I got a reading in excess of 100 volts (hard to read the scale accurately due to fluctuation caused by my shakiness touching the pins).  From this, I can presume that the inverter is still fuctioning?  When I plug the dead backlight back in, the whistle isn't there.