820-2936b no power no green light

tipoti

Member
On 820-2936b motherboard, no green light, no power.
U7000 19th & 20th legs, 5 volts. 14th leg 3.3 volts
U6901 4th & 5th legs 3.4 volts
 

tipoti

Member
I checked Pp... on R5301. 1st leg- 12.27 volts
On R5303 no voltage, is there supposed to be voltage? Also no voltage on R7978

16th leg of U7200- 12.27 volts
2nd leg of R7273- 3.3 volts
23rd leg of 7200- no voltage, no voltage on R7965 whatsoever
 

2informaticos

Administrator
Staff member
Your board doesn't turn on; there is no reason to check mentioned resistors voltage.

SMC_RESET_L goes high?
 

2informaticos

Administrator
Staff member
Post voltage and diode mode to ground on SCL/SDA lines of battery connector.
Don't forget to remove power when you check in diode mode!

BTW, do NOT quote an entire post, visible few centimeters above.
I don't see any reason to do that...
 

tipoti

Member
Post voltage and diode mode to ground on SCL/SDA lines of battery connector.
Don't forget to remove power when you check in diode mode!


I did as you asked. How else could I check it? Where was the black probe supposed to be? Could you elaborate specifically? Use exact instructions, please. Where exactly should I check with which probe? On which leg?
 

2informaticos

Administrator
Staff member
"How else could I check it?"
Read here...
 

tipoti

Member
Test in diode mode:
Connect positive probe of the multimeter (red) to ground and touch the test point with black probe.
Sometime (rarely) we need to test in reverse direction.


I sent it before 3.jpg

44.jpeg
 

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2informaticos

Administrator
Staff member
You've posted BEFORE SCL/SDA with BLACK probe to ground; OL and 2.176 respectively.

Now (in correct way) you get big diference between readings, 0.514/0.620.
Remove D6950 and check again.
 

2informaticos

Administrator
Staff member
Something else still bad there.
Remove C6952/53 and check again.
If still bad, then measure removing U7000.
SMC is the last to check.

Please, STOP to load such pictures; better to write the values.
 

tipoti

Member
When I touched the r7000, I noticed that the green light was on. When I unplug the charger and plug it in, it won't come back on.
 
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