MacBook Pro 13" A1502 820-4924-a

U7100 Voltages
MagSafe Only
Pin 1 - SMC_BC_ACOK = 3.395
Pin 2 - SMC_BC_ACOK = 3.150
Pin 3 - GND = 0
Pin 4 - SMC_BC_ACOK_VCC = 3.395
Pin 5 - PP3v42_G3H = 3.395
Battery Only
Pin 1 - SMC_BC_ACOK = 0
Pin 2 - SMC_BC_ACOK = 0
Pin 3 - GND = 0
Pin 4 - SMC_BC_ACOK_VCC = 0
Pin 5 - PP3v42_G3H = 3.391
Battery + Charger
Pin 1 - SMC_BC_ACOK = 0
Pin 2 - SMC_BC_ACOK = 0
Pin 3 - GND = 0
Pin 4 - SMC_BC_ACOK_VCC = 0
Pin 5 - PP3v42_G3H = 3.391
 

2informaticos

Administrator
Staff member
Put some logic on your job and avoid wasting time!
Any reason to measure U7001 with battery alone?
Did you ever see a Magsafe light on, in such case?

You lose SMC_BC_ACOK, good enough to lose the Magsafe light too.
Post basic U7100 voltages in that case; pins 1, 2, 3, 9, 12, 13, 15, 19, 20, 27.
Be sure no short between R7120/50.
 

2informaticos

Administrator
Staff member
You've said to get the problem ONLY when both charger and battery are connected.
Now make a guess, please...
 
U7100 with charger and battery connected
pin 1 = .019
pin 2 = .078
pin 3 = .019
pin 9 = 0
pin 12 = 3.390
pin 13 = 3.360
pin 15 = .060
pin 19 = 0
pin 20 = 0
pin 27 = 10.55

How do I check for a short between R7120 and R7150 please?
 

2informaticos

Administrator
Staff member
"pin 2 = .078"
Missing DCIN voltage.
Post Q7010 voltages.

Possibly original charger detects leakage, or overload.
Post PPBUS_G3H voltage only with charger.
Did you test with fake charger, or lab PSU?

Check resistance over C7120/50.
 
PPBUS_G3H charger only = 12.57
With lab PSU only and NO battery I get green then amber light but I can't get the board to power on (have tried powering on using the pads and also with keyboard)
It will, however, power on with lab PSU + Battery and the light does stay on the magsafe (amber)

I don't know how to give you the voltage readings for Q7010 as my board view shows a different orientation of the chip from my actual logic board.

c7120 = 28.49 mega ohms
c7150 = 3.8 ohms
 

2informaticos

Administrator
Staff member
"c7120 = 28.49 mega ohms"
Check R7121/22 and their traces.
Fix that; should be good enough to solve the problem.
 
R7121 and 22 were open circuit. Replaced both and problem solved.
You are an absolute genius! I don't know how you do it but I will read through our discussion and try and understand why you asked me to do the things you asked me to do.

Thank you very much!
 
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