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820-2850 green light no power
- Thread starter nate8organic
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nate8organic
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ppbus charger only - 3.2 volts slow drop down to 0.3v and stays at 0.3v
nate8organic
New member
okay your def right about that. checking s3 for voltages and not much has power.
i'm getting 3.3v on pin 2 & 3 of the q7210 but no power on pin 5 & 6.
Were does PP5V_S3 come from? im getting no power on l7220, c7250, and i cant test xw7220 because the schematics do not have it in the right place.
Thanks for the help so far!!
i'm getting 3.3v on pin 2 & 3 of the q7210 but no power on pin 5 & 6.
Were does PP5V_S3 come from? im getting no power on l7220, c7250, and i cant test xw7220 because the schematics do not have it in the right place.
Thanks for the help so far!!
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nate8organic
New member
tested pp5v_s3 and pp3v3_s3 and both are shorting to ground. tested by connecting led lights to the ground on the board and input 3.4 and 5v on the pp5 and pp3 rails. the only thing is i cant find anything heating up.. is there any tips on how to located the short?
nate8organic
New member
board 1
5v_s3 diode mode 0.432, or 23.5K ohms
3v3_s3 diode mode 0.423, or 113K ohms
board 2
5v_s3 diode mode 0.43, or 23.4K ohms
3v3_s3 diode mode 0.420, or 41.5K ohms
board 3
5v_s3 diode mode 0.425, or 23.1K ohms
3v3_s3 diode mode 0.420, or 46.9K ohms
5v_s3 diode mode 0.432, or 23.5K ohms
3v3_s3 diode mode 0.423, or 113K ohms
board 2
5v_s3 diode mode 0.43, or 23.4K ohms
3v3_s3 diode mode 0.420, or 41.5K ohms
board 3
5v_s3 diode mode 0.425, or 23.1K ohms
3v3_s3 diode mode 0.420, or 46.9K ohms
nate8organic
New member
i realized it was not a short when i took the resistance readings, guess i should have post that. the only thing i was wondering is why i got 113k on board 1 but only 46K on board 2 and 3. also wondering how i can get power through the ground though when i connect the power to the board. i tested power through the ppbus but nothing on the ground. its only when i inject power into s3 circuit do i get power to ground.
nate8organic
New member
Smc_adapter_en - 0 volts with power. res to gnd 9.8K or 0.539 in diode mode. same for all 3 boards. seems like the res is good.
nate8organic
New member
as far i know its been a real 85w charger. but i guess i could be wrong here is the specs of the charger: UL Japan ADP-85ebt v85 Delta electronics (jiang su) LTD. it powers on all the 15 and 17 inch boards i get in every time. the charger really has an effect on putting power to ground? because i tested other 15 boards i have in and non of them put power through the ground and its the same charger.
nate8organic
New member
Yes, it does. i have fixed a few 15" boards over the last few days and test all of them with the same charger so i know for sure the charger is working for other boards with and without the battery installed. also i did a smc by pass on one board with a keyboard installed and the fan just glitches like before so the smc is good at least.
G3h is getting vacuumed down to nothing and it only read 3.4 ish volts when i plug in and test and its dropping in volts so fast it has to be going somewhere. but not on the g3h rail, so somewhere after that, can it be before the G3h line that the power is getting drawn?
Appreciate the time and response!
G3h is getting vacuumed down to nothing and it only read 3.4 ish volts when i plug in and test and its dropping in volts so fast it has to be going somewhere. but not on the g3h rail, so somewhere after that, can it be before the G3h line that the power is getting drawn?
Appreciate the time and response!
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nate8organic
New member
Customer just sent me in another 2850 with this same issue so i now have a total of 4 boards with the same issue here. kinda wondering how i'm getting so many with the same issue but having so much trouble finding it. Also so far this has only been on the I7 boards i have gotten in, don't know that it can make a difference but throwing it out there.
if SMC_ADAPTER_EN is low, you have two options.
bad SMC
bad charger/dc in board.
I pray for your sake it is the second.
I have seen knockoff chargers cause the machine to not turn on, sure, but never seen them cause the thing where ppbus goes down to 0-4v. when it is not the traces between pins 17/18 or 27/28 of the isl6259 on 2850 boards it is often a nightmare.
bad SMC
bad charger/dc in board.
I pray for your sake it is the second.
I have seen knockoff chargers cause the machine to not turn on, sure, but never seen them cause the thing where ppbus goes down to 0-4v. when it is not the traces between pins 17/18 or 27/28 of the isl6259 on 2850 boards it is often a nightmare.
nate8organic
New member
larossmann Thanks you for the info! if i do a smc bypass by holding the power button down on a keyboard and then dropping the power to the board it kick on the fans they still glitch but get a good spin going and i test the ppbus and g3h rails and everything is working 12.5 volts on the ppbus_g3h. is this a confirmation for the smc as the problem?
Of the 4 boards i have like this all of them give 12.5v on ppbus_g3h and 18v on pin 28 of the 6259. when performing the smc bypass 1 board spins, 1 just glitches consistently, 2 do not move at all. i am guessing a few have other problems on top of the smc. can i heat the smc to see if it just something fcuking up a ball?
Thanks again! and happy Easter man! i think the damn easter bunny left the egg right in front of me on this one and it was rotten inside...
Of the 4 boards i have like this all of them give 12.5v on ppbus_g3h and 18v on pin 28 of the 6259. when performing the smc bypass 1 board spins, 1 just glitches consistently, 2 do not move at all. i am guessing a few have other problems on top of the smc. can i heat the smc to see if it just something fcuking up a ball?
Thanks again! and happy Easter man! i think the damn easter bunny left the egg right in front of me on this one and it was rotten inside...