Dell latitude e5440 shutdown after 3 sec

[hpibmx]

Hi,
I put my laptop on sleep for few days didn’t wanna miss where I left.
Yesterday just pressed power button came on high fan and shuts down. Just all of sudden Sutton on my table.

I’m repairing phones and tablets. Not experienced with laptops.

I’ve look around motherboard for short didn’t really find anything.

What would be the cause?
Thank you.

[mikerj]

Go through the basics, remove memory modules (ideally one at a time if there are two), hard drive etc. and see if behaviour changes.

[hpibmx]

Sorry forgot to mention yes I’ve done all those. Still the same

[abdulbadii]

thermal paste age ? feel the heatsink if not hot ~85 C so overheat too soon

[amyk]

Unplug, remove the battery and hold down the power button for ~30 seconds to drain any residual charge for a true cold reset.

OEM model is Compal LA-9832P. You'll find the schematic if you search for that. Power rails and sequencing information can be found there.

[McBryce]

Check the PCB for cracked ceramic capacitors, especially around the area of the power switch. I've seen this on several laptops that had the same symptoms.

McBryce.

[hpibmx]

Yes correct about 4 months old. And a free diagnosing I put them back to prevent quick overheat. Thank you

[hpibmx]

Unplug, remove the battery and hold down the power button for ~30 seconds to drain any residual charge for a true cold reset.

OEM model is Compal LA-9832P. You'll find the schematic if you search for that. Power rails and sequencing information can be found there.

I’ve done that too, yes that’s correct and have downloaded the schematic was looking for brd file as well but I guess no need. I’ve looked everywhere done my measurements didn’t find any short at all. On main power rails. Around cpu around gpu. Lower resistance but no short at all. I’ve 3.3v present 5v and 19v.

[hpibmx]

Check the PCB for cracked ceramic capacitors, especially around the area of the power switch. I've seen this on several laptops that had the same symptoms.

McBryce.

Okay I’ll go through again and look closely but really couldn’t find any faulty cap.