Perform the generic reset too. Power off, remove ac, battery, press hold the power button for 60 seconds, release, apply AC and re-test.
The long version of this is in the top of the CNET Laptop Troubleshooting forum.
I have a Dell Studio 1735 with an interesting problem. When the power cable is plugged into the pwr jack the blue pwr light comes on for about 1/2 second and then goes out. I can do this repeatedly with the same results. I know that pwr connectors on laptops are more than just a small issue but, I've never seen one behave like this. Before I break this one down and replace the jack HAS ANYONE SEEN THIIS BEFORE? I have a "feeling" that there is much more going on. The battery will not charge either...understandable. If I remove the battery same results.

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