Aspire 1640 reversed polarity repair help

Hi guys, I screwed the MB of my laptop with one of those stupid universal adapters, I accidentally connected the polarity in reverse, now the laptop runs perfectly with the AC connected properly but the battery will not charge, windows shows me "connected with AC, charging xx%" and xx is decresing slowly (no power is going to the battery connector) the laptop still runs with the remaining charge of the battery and will work if the adaptor is on, so that is the one and only symptom that the laptop has. I assume that when the polarity was reversed it blew diode or something. I read on other sites that laptops have polarity reversal protection by having a diode and a fuse that burns out so it won't fry the entire board. I'm guessing it only affected the battery charging circuit as everything else works ok.

I'm looking for help because maybe some of you know these boards on a component level and can help me find out which component to replace, this is the second board I buy I'm not willing to spend money on a third so I really want to replace the affected part, I can only find one fuse near the power connector I'm guessing that one is ok or else the laptop wouldn't work with AC power, I sending a photo to see if any electronic wiz could help me identify some parts.

Is it possible that all it needs is a diode replacement?

Sorry for the blurry photos but my camera isn't that great with macro photos

 

Those are SMT electronics my friend .

You can not touch them, with out special tools.

I have knowledge in electronics , but the point is that no one can tell anything, from just a picture .

I predict that you had injured the micro controller responsible for the battery .

I can not tell who it is , but it should be an IC , driving few Mos fet .
The IC can not handle DC current , thats why the Mos fet gets in the way, they do the hard job.

 

Great just my luck, so there isn't any kind of protection before that IC?

 

The IC's are always more sensitive than the diode's .

You need help from an electronic engineer , to check the circuitry .

 

I found a cheap motherboard of the same model but the only thing wrong with it is the graphics section, if I were to buy this board could anyone give me some pointers of which components to replace? Other than the IC and the mosfets? I've tested the outputs of the battery with a voltmeter and no current is there, only about 3V on the central pins which I guess is what tells the PC if the battery is inserted and how much charge is left, but the positive and negative has nothing. But I've tested continuity between positive and negative and there is continuity so I guess they're in short circuit. Should replacing the IC and MOSFETs be enough?

Please look at the photo, I think the surrounding resistors test ok too or at least there is continuity, how do you test the IC and the mosfets?

 

Its a lost cause t0nito

You cannot test an IC without a socket. Lappies use SMD. Soldered to the board. And the boards are multiple layered etc.

Thats why motherboards are replaced and not repaired when faulty.

Sorry

Theo

 

t0nito your unknown part (like black tower ) its a coil = voltage filter.


I all ready advice you , finding a Pro to do the testing ...

Your interference with it , can cause more damage than good.

 

Well ok then, thanks guys, I guess I'll have to keep searching ebay for a motherboard, no way I'm gonna buy a motherboard for the price of a new laptop...