Apple MacBook Pro / Board 820-01700 short on ppbus_g3h

[Roshon]

i removed f7000 and f7001 the short on ppbus_g3h
L9080/580. no short
L7330 = 0.006
L7231 = 0.002
LA950 = 0.013
LA870 = 0.012

 

[2informaticos]

What's the reading of that short?

 

[Roshon]

0.004

 

[2informaticos]

Check resistance between PPBUS_G3H and L7211-31.
Do you get 0.002?
Possibly one of U7210-30 is burnt.

Did you check resistance to ground at UA710-40 too?

 

[Roshon]

resistance between PPBUS_G3H and L7211 =0.001
L7231 = 0.001
BOTH U7210 AND U7230 HAVE ALL THE SAME READING ON ALL PINS SOME HAVE 0.003 AND OTHERS MUCH HIGHER

IS UA710 UNDER HEATSINK IF SO HOW TO REMOVE

 

[2informaticos]

Looks like you have one of U7210-30 burnt.
Lift one side L7211-31, to detect which chip is the culprit.

 

[Roshon]

L7231 PIN 2 PPVCC= 0.008
PIN 1 CPUCORE 1.895 AND GOES UP
L7211 PIN 2 PPVCC =0.009
PIN 1 CPUCORE 1.786 AND GOES UP

 

[2informaticos]

Didn't find L7221???

 

[Roshon]

l7221 pin 2 =ppvcc 0.005

 

[2informaticos]

Looks like U7220 is burnt.

Still short on PPBUS_G3H once L7221 is lifted?

 

[Roshon]

when i lift L7231 the short to ppbus_g3h goes away

 

[2informaticos]

Then U7230 is the culprit...

 

[Roshon]

when i lift L7231 the short to ppbus_g3h goes away BUT PIN 2 PPVCC_CPU_PH3 IS SHORT TO GROUND PIN 1 CPUCORE_SW3 IS NOT

 

[2informaticos]

"PIN 2 PPVCC_CPU_PH3 IS SHORT TO GROUND"
What's the problem?
You've said to have correct 0.008 there...