820-2915 dim green light missing p3v42

[Chuck60]

Hi I have a dim green light and didn?t find p3v42 at L6990
u6990
2 p3v42_fb =3.7v
3 p3v42g3h_ton = 15v
4 ppvin_g3h_p3v42g3h =16.5v
6 p3v42g3h_sw =0v
7 ppvin_g3h_p3v42g3h =16.5v
8 p3v42_fb =3.7v
9 p3v42_g3h =0v
10 p3v42_ref3=0v

 

[2informaticos]

Post first diode mode to ground at L6995.
If OK, check/replace C6991/95.
If still the same, change U6990.

 

[Chuck60]

Diode mode .003
i removed c6991, c6995
i have the same .003v on pin 2 of l6990
I see in the schematic that it goes to all the board so it?s either smc or this chip u6990 I?m hoping it?s the chip but my gut feeling is the smc I will pull the chip and report back

 

[Chuck60]

Removed u6990 still .003v

 

[2informaticos]

I mentioned that caps if OK value at 3V42 line.
Why did you touch them, if short???

Enough low value, so easy to find the culprit injecting voltage.
Start with 1V, no more than 3.8V max...

 

[Chuck60]

Ok I found a issue :/ c5750 and u5750 I powered it up and got 12.57 the mux got hot and it?s no fan spin. How Important is this smc manual reset chip or can I continue to diagnose till it arrives.

 

[Chuck60]

Oh and steady green light on charger

 

[Chuck60]

P3v42 is =3.42
ppbus_g3h =12.57

 

[Chuck60]

So it?s no short on r5071 smc_lid it?s on pin 2 so I?m glad that the smc is probably ok u5010 on pin 1 is .003v so it?s either the chip or c5020 I don?t like heating near mux what?s you opinion on removing this cap and or u5010

 

[2informaticos]

Both U/C5750 shorted?

U5750(55 are only used to do manual SMC reset with keyboard.
You get same thing removing charger and battery.
Of course, no need to remove battery, doing SMC reset from keyboard.

 

[Chuck60]

Not both one of them I?m guessing is shorted

 

[Chuck60]

Honestly i removed u5750 and the pin that goes to r5071, u5010,c5020 is .003v to ground. As I?m reading the schematic I believe it?s either u5019 or c5020 I was wondering about heating up near mux since it has underfil how easy is it to mess the the mux up?

 

[2informaticos]

Use alcohol method and you should be able to locate individual component which fails.
Videos available on Internet; Louis had something on the channel I think...

 

[Chuck60]

Honestly because when I use the power supply the same part c5750 overheats. I change it with the same if I remove c5750 and power it up the mux gets hot