XPS M1330 Power Failure

Hi, I have ~3 years old M1330, that doesn't charge the battery (it's empty now). Also with no battery and AC adapter connected, the laptop doesn't start. With the battery connected, when I press the power button, the amber light, on the front panel, goes on, indicating that the battery is empty.

This kind of problem happened before, and the laptop was sent to Dell, they said that they replaced the MB ($450 ). This fixed the problem for a ~1 year. Now it's failed again. I tried the adapter on other laptop and it worked well. Also tried other adapter on the failed laptop, and it didn't worked.

Prior to complete failure, the power from the adapter were "loose", sometime it did charge, and sometime it did not, wiggling the connector from the AC adapter was fixing the problem (exactly same, as the previous problem).

My first suspect was the loose connection inside the power socket inside the laptop, or bad solder. I disassembled the laptop (in a lab conditions). Tried to "refresh" the solder. But it seems that they use rohs (high temperature solder) and I wasn't able to melt it at 900F.

Then I measured voltage on the board, next to the adapter socket, and it seemed fine: 19-19.5V, so the power from adapter comes to the motherboard. Also I ordered and tried new DT2 charger-usb board (the one that has charger IC) and the results were - laptop doesn't start and the battery isn't being charged.

Does anybody have any suggestion I can try, prior to ordering new MB?

Are there only two leads (+ and -) coming from the AC adapter, or there is third - digital signal that allows laptop to ID the adapter?

Thanks!

 

Next to the Nvidia GPU issue, these sorts of power issues were the next most common on the M1330, etc. If you've tried a known good adapter, a known good battery, resetting the CMOS, etc, and it still doesn't work, you probably need to buy a new mobo.

Don't buy it from Dell, though. $450 is already more than the worth of the entire laptop, even a year ago. Even on eBay a working board currently runs for maybe $100, which is a quarter to a third of the value of your machine (depending on spec), so keep that in mind...

 

Thanks for the suggestion Commander!

Today, I went through the power path on the MB, using scope and microscope. And actually found the broken solder on the L31 component (part that is very close to the AC adapter):



To me, it seems like the root of the problem: solder broke due to flex of the MB, due to movement of the AC jack , and moving the AC adapter jack would fix the problem, on early stages.

So, I re-soldered the part, and tried charging the battery, using only MB + Charger Board [CB], the battery would not charge. Then I tried to apply 12.6V limited to 750mA, 1.5A, 3A, 200mA (precharge), to the battery + and - leads, while connected to the MB + CB. The battery wasn't charging. Also I wasn't able to charge the battery standalone (using only smart battery charger). I wasn't able to communicate to the battery using SMBus adapter, neither saw SMBus communication (using scope), when the battery was connected to the CB, and CB+MB.

The battery still outputs 10.2V, but it seems like it doesn't take any charge .

Anyways, after resoldering the broken solder, I did assembled the laptop. It wasn't charging the battery, when battery connected. But, when AC connected, and I press the Turn ON button, the blue light comes on, on the front panel, I can hear and feel that the HDD and DVD starts, some very quick LED blinking... it seems like the power works. But the screen doesn't come on, and the CPU fan isn't turning.
I tried to start the laptop with no RAM and no CPU, and was getting specific LED blinking patterns, so it seems like the system is aware that the RAM and the CPU are present, but doesn't start for some reason.

Any ideas?

Does anybody know if the laptop would start with no battery connected (I tried to power on with and without the battery, but I question if the battery alive at this point)?

Should I get new battery and try it with known good battery?

PS: I hear you Commander, I don't really want to spend more than $100 (100 - is for "fix it for sure" solution) on this laptop. I even would take AC-only solution.