Apparently there may exist a problem with "L" key on Dell Inspiron keyboards. I have an almost new 6000 that had "L" key problems, mainly just not typing at all. You can scroll down and read my posts, including the awesome customer support by Dell. In short, I emailed Dell and had a new keyboard in my hands in almost 24 hrs via Airborne Express (DHL)!!! Hope this helps!
I ha5ve the similar problems with many keys.
6m 5v -\ =,
also some keys are not working such as letter after 'w' I cannot type !