L511Z not charging

I have seen dozens of people with the same problem. Some have either had to buy a new mobo or DC power jack, but most (not L511z owners) get by with reflashing the BIOS.

Anyway, it's the usual story. The PC will run off mains power happily enough, the battery is now down to 22% as I use it on the train and the power keeps cutting out. I have tried it with three different chargers, including my daughter's and she has the same model as mine.

I find it hard to believe that the motherboard is genuinely borked, but if it is it's pretty bloody apalling given that the thing is just over 2 years old (and just out of warranty). The cheapest refurbished i7 mobo I have seen would cost me around €270 / $370, so I would like to try a reflash of the BIOS.

Of course, this is where it gets sticky. I cannot run the BIOS upgrade. It complains that the laptop must be plugged in, which it is, but of course the idiotic software checks for that and thinks that it's not plugged in. thus I cannot continue.

I have tried pretty much everything, even running from a DOS bootable USB stick, though I knew that wouldn't work. Whatever I do I always end up with either "The AC adapter and battery must be plugged in before the BIOS can be flashed" or some kind of error I can't identify when I run it in compatibility mode.

I have obviously tried running in a command window, with the parameter /forceit which I had hoped would work, but no, the parameter appears to be useless.

I can buy a power jack for about £30 / $50 but if it really is the mobo I have just wasted another week and $50. Which raises the question as to why are Dell parts only available on ebay US, so I always have to pay import duty?

Obviously I will buy a motherboard if I have to, as I need a PC I can carry around without it powering down whenever I unplug it, but I would much prefer to give the BIOS fix a shot first. I mean, if the motherboard is fine except for BIOS Dell should feel ashamed that I have to bin it because their inbuilt limitations prevent me from using it.

I have to say that this peeves me a lot, and I may give this machine to my wife, who doesn't care about technology, and move to Samsung, but even my wife would like a battery.

So, does anyone have another idea? Is there a way to spoof the flasher into thinking that it's plugged in even when it really is? Is there a genuine /forceit parameter? Is there any reason I should not just give up on Dell?