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Mystery part from an HP Laptop Mobo

Hello There,
I'm attempting to fix a laptop that was dropped hard enough to break this component off of the motherboard:

http://i960.photobucket.com/albums/ae81/dopey-robot/Misc/DSC02215.jpg?t=1284778186

I don't know what it is, therefore I don't know what it does. But I want to know so I can replace it if possible or at the very least learn something about it. The circuit board is marked "TC11" where this component goes, if that helps. Also, it appears to be polarized as it's marked with a grey band at one end which you can't really see in the picture.
Thanks
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
Has someone tried to solder it back in place?

It's probably a diode or a capacitor. Some trivial tests with a multimeter will allow you to eliminate one or both of these possibilities.

The next step is identifying the type/vale of the component.

A picture showing where it came from may be helpful.
 
btw this is not my laptop to be clear, I'm simply looking at it for someone but I think I'm starting to figure out what happened. I don't think this laptop was dropped as was told to me by the owner because there's no external damage. Here's a picture of one of the two memory modules that come out of it:

http://i960.photobucket.com/albums/ae81/dopey-robot/DSC02262.jpg?t=1284823598

That shinier line near the keyed slot on the gold contacts is a fairly deep gouge made by something hard and pointed(possibly a screwdriver?).

Here's my theory and tell me if you think it might be correct. When the power button is pressed, one particular LED flashes three times each time you press the power button. A quick search on HP's site indicates that three blinks correlates to a problem with a memory module. The part that came off the board is directly behind the slot that holds the modules. I didn't take a pic of the underside of the part, but it came off violently as far as I can tell. I'm starting to think that initially there was an issue with the laptop, the owner looked up the meaning of the three blink error code and opened the cover in an attempt to fix it. Then, when he/she(it's a mother and son and I don't know which one's the culprit yet but my money says it was the son lol) couldn't get the memory modules out properly they tried using something to pry them out but slipped and hit the component in question which broke it off of the board.

That's my theory anyway, I guess one thing that could shoot a hole in it would be if the three blink error code is directly related to the component, but somehow I don't think so.

One more thing, Is it possible that this part has something to do with temperature sensing? The TC marking maybe means "thermal controller" or "thermocouple"? I'm stretching here I know, just a thought.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
OK, you need to measure the component with a multimeter and see what it is.

If your multimeter reads capacitance values, even better, but just the resistance at first would be great.

It looks to me like it might be a capacitor.

I hope that apparent bend in the memory module is just pincushion distortion.
 
I can't give you capacitance values, but it reads 162 ohms with the probes orientated positive to grey band, and 158.5 ohms reversed.

[update] it's definitely a capacitor. I have another laptop board(dead) lying around and it has a nearly identical component on it and the board is marked cxxx. I don't understand the code system they use though, it's always starting with "NE" and then a lower case letter(I've seen an e and an h so far) and then some combo of a j, an 8 and another letter. Does anyone here know the key to deciphering these markings?[/update]
 
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Seeing the pics I can definitely say that it's a bypass capacitor but NOT RESISTOR!!. It doesn't look damaged to me in the pics, why don't u solder it back? Watch for correct orientation before soldering it back.

And you should be getting infinite resistance in this part if you stick probes on it long enough. Did you burn it when attempting to solder?
 
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I did initially attempt to solder it back into place, and although my soldering skills are not altogether pitiful, I may have damaged it further in the process. My real curiousity now is in deciphering the scheme used on these components to denote its values of voltage and capacitance. All my efforts to learn this coding scheme have been met with futility up to this point. To me it seems to be an attempt by the manufacturers to obscure the correct values, probably to discourage smaller repair shops etc. from fixing them, so as to force the end user to buy a new laptop. That's my theory anyway.
 

(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
Moderator
The parts are generally too small to place all the information on them.

Added to that, they are often assembled by machines and not intended to be repaired.

If you're really lucky you'll get a cryptic code that will lead you to the specs, often there are no markings at all.

It's probably more that the equipment manufacturers are trying to drive down costs, and do not demand markings, so the component manufacturers can shave another hundredth of a cent off their costs by not marking them.
 
Ok, I apologize for not paying attention to the replies to this thread, 'cause about four replies back Scotty answers everything with links to a .pdf! Thank you, thank you & thank you once more for shining light on this mystery!
 
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