[SOLVED] What exactly happened to my motherboard? (weird liquid-y looking burnt spot found after it stop booting up)

[Alenna]

Hello folks,

Some time ago I was tasked with repairing a laptop at work. It's a Hp Probook 450 g3. The power button was not working. I followed the guide to the letter, made sure I was grounded, etc. Was relatively simple. I reassembled it, and it booted it, no problem.

I left it running to do updates, etc.

It waited to be returned to it's former owner, but when I went to boot it back up I was greeted with a series of two long beeps and two short beeps. I look over the diagnostic codes for the model and make, and tried all suggestions.

I figured maybe I need to reopen it again, maybe I failed to reconnect some of the cables. So I did and was greeted to this blobby dark murky blotch! I was confused, for a moment I thought may be I left a piece of tape, but the tape I used should not have been conductive. My boss confirmed this as well!

I am not certain if this blotch was originally there, I would've noticed it, surely! Lastly the fact that I did open up another same make and model of laptop and it did not have this blotch. What could have went wrong? Is this potentially my fault? Is it possible the tape was conductive and a piece was left on there and melted? I can't peel or scrape off this blobby burnt spot either.

Some insight would be greatly appreciated, thanks!

quick edit: I should note, this image makes it seem way more larger than what it is! It's far smaller considering it is a laptop motherboard.

 

[lynx1021]

Didn't see an image, maybe a capacitor leaked out or some one spilled something on it while you were gone.

 

[Alenna]

You can't see image? Hm, I can see it. Here is just direct link:

https://i.ibb.co/KGRR1xZ/20190702-131451.jpg

Still can't see?

 

[drea.drechsler]

Hello folks,

Some time ago I was tasked with repairing a laptop at work. It's a Hp Probook 450 g3. The power button was not working. I followed the guide to the letter, made sure I was grounded, etc. Was relatively simple. I reassembled it, and it booted it, no problem.

I left it running to do updates, etc.

It waited to be returned to it's former owner, but when I went to boot it back up I was greeted with a series of two long beeps and two short beeps. I look over the diagnostic codes for the model and make, and tried all suggestions.

I figured maybe I need to reopen it again, maybe I failed to reconnect some of the cables. So I did and was greeted to this blobby dark murky blotch! I was confused, for a moment I thought may be I left a piece of tape, but the tape I used should not have been conductive. My boss confirmed this as well!

I am not certain if this blotch was originally there, I would've noticed it, surely! Lastly the fact that I did open up another same make and model of laptop and it did not have this blotch. What could have went wrong? Is this potentially my fault? Is it possible the tape was conductive and a piece was left on there and melted? I can't peel or scrape off this blobby burnt spot either.

Some insight would be greatly appreciated, thanks!

quick edit: I should note, this image makes it seem way more larger than what it is! It's far smaller considering it is a laptop motherboard.

Might try using one of the most sensitive chemical analysis tools you have at immediate disposal: your nose. What does it smell like? The odor of burnt electronics is quite easy to detect.

If you (or someone else) spilled something on it it would probably smell sweet or maybe like coffee or soda and would be sticky to touch.

Lastly: it obviously doesn't belong. Clean it up with some IPA and distilled water and soft bristle brush and blot dry with soft tissues if you can. That alone might... or might not... fix it. But at the least it would allow better imaging and identification of the device that may have burnt. That would be the black squareish object dead center of ground zero.

 

[Alenna]

Might try using one of the most sensitive chemical analysis tools you have at immediate disposal: your nose. What does it smell like? The odor of burnt electronics is quite easy to detect.

If you (or someone else) spilled something on it it would probably smell sweet or maybe like coffee or soda and would be sticky to touch.

Lastly: it obviously doesn't belong. Clean it up with some IPA and distilled water and soft bristle brush and blot dry with soft tissues if you can. That alone might... or might not... fix it. But at the least it would allow better imaging and identification of the device that may have burnt. That would be the black squareish object dead center of ground zero.

There's no different smell from it than the rest of the motherboard. I touched it, and it's not even sticky. It's hard to the touch. I hit it with IPA and tried to gently scrub it off. It's not even coming off.

I think this laptop originally went in for repairs, could this be a bad soldering job? It looks like it is coming from the chip, or perhaps is that a capacitor?

We have many more of these models at my work place...is this just a one time thing? Do capacitors often so easily go bad? Is there anything I may have done to accelerate the process or simply just bad luck? These laptops are almost three years old. But we found so many issues with them so far...I would hate to add this as another thing to look out for on the list.

 

[drea.drechsler]

There's no different smell from it than the rest of the motherboard. I touched it, and it's not even sticky. It's hard to the touch. I hit it with IPA and tried to gently scrub it off. It's not even coming off.

I think this laptop originally went in for repairs, could this be a bad soldering job? It looks like it is coming from the chip, or perhaps is that a capacitor?

We have many more of these models at my work place...is this just a one time thing? Do capacitors often so easily go bad? Is there anything I may have done to accelerate the process or simply just bad luck? These laptops are almost three years old. But we found so many issues with them so far...I would hate to add this as another thing to look out for on the list.

If you can't detect the usually very obvious aroma of burnt electronics then it's doubtful anything's burnt. A good sign, at least.

Can you get in really close to read off the numbers of that device? A Google search on them might reveal some good information.

Also: what fits on top of that board? a pulled-out picture showing the assembly better might help figure out where it comes from.