820-2879 No power on one USB port [solved]

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Puevig reven

New member
I have a 820-2879 with no power to one USB port. No water damage, I measured PP5V_S3_RTUSB_B_ILIM at pin 6 of Q4690 and I get .070 and pin 7 measures 5.0V. I replaced Q4690 and same thing. I also have 3.3 at both enable pins on Q4690. Any ideas???


with your DMM in diode mode red probe to ground measure pin 1 from J4610, report value.....
Is something getting hot?????
If every thing is ok, then you have a bad Q4690 or wrong soldered


Pin 4 is ok cause it is ground, but pin 1 is shorted, you can remove L4615 and see in which pin is the short, if is on pin1 problem could be C4615, C4616, C4617 or Q4690 again, if the short is on pin 2 the problem is D4610.


Staff member
Gives you a reading of what?

What reading do you get and what mode is the meter on for this? On diode mode, red probe on ground, black probe on

1) pin 1 of L4615
2) pin 2 of L4615
3) pin 1 of L4605
4) pin 2 of L4605

I just want to make sure no confusing nonsense is being missed in the measuring process here.
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