Hey all.
Scored a HP 6715s untested base with battery for £6! No reason, just wanted something to play around with haha.
Disassembled it and there appeared to be minor water damage around the DC jack, some kind of solidified sticky residue around there.
I've done some multimeter testing and identified a faulty transistor right next to the DC jack - Q75, an SSM3K7002F. It only reads on one leg, and infinity on the other - identical surrounding transistors read fine on both.
I've grabbed the section of the schematic containing Q75/DC jack components and stuck it up here: http://www.mediafire.com/view/?kdsyx63e3ccquib
^On that diagram, the faulty leg on Q75 is #3, the one connecting to R75, Q13 etc.
Here is a photo of the board in question (blue depicts where the residue was, circled in red is Q75):
The laptop, as it stands, is completely dead - no lights whatsoever, on DC or battery (though the battery may just be discharged, I am not sure). I accidentally shorted something with the multi and the power light/charge lights kicked in very briefly and died again.
1) Would Q75 being faulty cause these symptoms?
2) What can I replace it with? I cannot seem to source it though I do have plenty of scrap motherboards with transistors available.
3) Would I be able to short across the faulty leg briefly to see if it comes to life?
Cheers!
Scored a HP 6715s untested base with battery for £6! No reason, just wanted something to play around with haha.
Disassembled it and there appeared to be minor water damage around the DC jack, some kind of solidified sticky residue around there.
I've done some multimeter testing and identified a faulty transistor right next to the DC jack - Q75, an SSM3K7002F. It only reads on one leg, and infinity on the other - identical surrounding transistors read fine on both.
I've grabbed the section of the schematic containing Q75/DC jack components and stuck it up here: http://www.mediafire.com/view/?kdsyx63e3ccquib
^On that diagram, the faulty leg on Q75 is #3, the one connecting to R75, Q13 etc.
Here is a photo of the board in question (blue depicts where the residue was, circled in red is Q75):
The laptop, as it stands, is completely dead - no lights whatsoever, on DC or battery (though the battery may just be discharged, I am not sure). I accidentally shorted something with the multi and the power light/charge lights kicked in very briefly and died again.
1) Would Q75 being faulty cause these symptoms?
2) What can I replace it with? I cannot seem to source it though I do have plenty of scrap motherboards with transistors available.
3) Would I be able to short across the faulty leg briefly to see if it comes to life?
Cheers!
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