Latitude E5540 motherbaord short

[simonknights]

Hello,

I have a latitude E5540 and unfortunately whenever I connect the power the light goes out on the PSU. I have tried from battery and it still won't switch on. I assumed it may be shorting on the case soemwhere. I have stripped it down and removed the motherboard but still the light goes off when the psu is connected to the jack. Unfortunately it is outside of warranty, is there an easy way to determine if it's a single component which has failed which I could remove and solder a new one on?

Any help would be appreciated.

 

[Lutfij]

The sad bit with laptop motherboards, is that you will need a certified technician to verify the issue. To me, it's as if the power brick is failing at it's duties, provided what you've explained is the power bricks LED and not the power indicator LED on the laptop.

 

[simonknights]

The sad bit with laptop motherboards, is that you will need a certified technician to verify the issue. To me, it's as if the power brick is failing at it's duties, provided what you've explained is the power bricks LED and not the power indicator LED on the laptop.

Unfortunately the power brick is ok as I have tested it on another laptop. I guess it needs a new motherboard or I take it to a specialist.

 

[J_Walker]

Old thread, but just thought i'd mention that I've now had 3 Latitude E5450's at work that have had this problem. In all cases, the motherboard was the issue, likely a diode or something at the DC input power failed and is shorting and thus is tripping the short circuit protection in the PSU (which is why the PSU led goes out right when you plug it in). In all cases, the AC adapter/PSU was fine and the DC plug on the laptop was fine as well.