Help finding the lid (backlight) switch. Presario C500

[Lucky13ESP]

My sister has a Compaq Presario C500 notebook.  It is out of warranty coverage.  One day my sister shut the cover as she traditionally does and when she opened it again the next day, there was no backlight.  You can still see a faint image when held at the correct angle with some ambient light.  I hooked it up to an external monitor to double check this and the computer is outputting the signal fine.  So I've narrowed it down to three things.

1. Lid switch that automatically turns off the backlight
2. Inverter, supposedly fails more often the backlight
3. The actual backlight

 Now I'd like to rule out the free option before I start picking up replacement parts.  However, I cannot find the darn switch.  I've taken the laptop apart completely and I just can't seem to find anything.  Please help me as she'll be bugging me until I fix it.  If/when I rule out this switch, I'll proceed to the more expensive possibilities.  Thank you very much.

[Lucky13ESP]

Anyone with any insight about this?

[Pugzly]

If its anything like my dv9000 you will find it on the cooling fan shell. It is only about 15mm long and about 8mm wide. Is either stuck on with doublesided tape or one screw. Has a wire harness (small) that goes to power switch. It is operated by, I think, a magnet in the bottom of the screen cover. Hope that helps you out.