I have the same exact problem. The laptop is running on the battery fine but doesnt work on AC adapter.
I check the jack. It's giving the requisite voltage(18V). So the jack is fine. Then I checked the diodes. The same diode that was open o your mobo was open on mine as well giving a voltage of about 16V measured both ways. Which means its open if I am not wrong.
Now I need a diode that I can connect in parallel but I don't know what store to buy them from.
I tried radio shack but they have limited items.
Can anyone suggest the replacement diode and the store I can get that diode from??
Buying it online will take some time till I get it.
Forgive me Saran28 if I post to you, and rms59 at the same time.
@rms59, YOU are my HERO!
That's what I'm TALKING about. A REAL tech!
I would have thought the power correcting chipset, (May not be accurate nomenclature), took a hit.
This is one example of which I am referring to, a Power MOSFET used in a lot of laptops,
(Correct me at any time, rms59. I am a fledgling, and can take constructive criticism well)
I suggest Mouser Electronics. Radio Shack is VERY limited,