Macbook Pro A2141 820-01700-05 Wont turn on.

cpuentes23

New member
Ok, I havent gotten the T2 replacement yet but I releived the short on PP1V8_SLPS2R rail, PPBUS_G3H still shorted to ground, Any suggestion? Thanks.
 

cpuentes23

New member
I know!

PPBUS_G3H to ground: 21 Ohms.
PPBUS_G3H to CPU coils: 21 Ohms
CPU coils to ground: 1.7 Ohms

Would be safe to inject 1V into PPBUS_G3H?
 

2informaticos

Administrator
Staff member
Did you check diode mode (or ohm scale) disconnecting charger and battery?
Check if any other big coil shows 17 ohm to ground.
Don't forget L9080/580.
 

2informaticos

Administrator
Staff member
So actually your board doesn't turn on.
What you did to happen this?

Be very sure no short between PPBUS_G3H and any other coil; or you can fry the board injecting voltage!

Just for refference:
L6960/61 424
L7030 501
L7211/21/31 003.2
L7330 031.8
L7410/20 009
LA710/20/30/40 003 / 8.5 ohm
LA750 004.9
LA850 032.7
LA860 041.8*
LA870 042
LA950 024.6
L7600 412
L7660 387
L7701 140
L8102 128
L8410 882
L9020/21 467
L9030 372
L9080/81 424
L9520/21 426
L9530 373

Missing L3500, L9580 and LB700 in the listing; check them too.
 

cpuentes23

New member
I did nothing, at the beginning I was thinking it was something related to SSD's just as many people claimed on internet. I also thought U7000 had something to do about it but it was Ok. Wasn't expecting to see PP1V8_SLPS2R shorted! That's it :).

So, for:

L6960/61: 6 Ohms
L7030: 45.2 KOhms
L7211/21/31: 1.6 KOhms
L7330: 37 Ohms
L7410/20: 26 Ohms
LA710/20/30/40: 21 Ohms
LA750: 24 Ohms
LA850: 49 Ohms
LA860: 49 Ohms
LA870: 49 Ohms
LA950: 37 Ohms
L7600: 7 KOhms
L7660: 2.9 KOhms
L7701: 258 Ohms
L8102: 80 Ohms
L8410: 32 KOhms
L9020/21: The Ohm reading fluctuates up and down like crazy from 172 Ohm to 2.2 KOhms
L9030: 2.8 KOhms
L9080/81: 7 KOhms
L9520/21: 259 Ohms
L9530: 147 Ohms
L3500: 8 KOhms
L9580: 3.3 KOhms
LB700: 8 KOhms

Thank you!
 

2informaticos

Administrator
Staff member
I posted diode mode readings for refference; just one ohm value, for very low reading.
Why can't do the same?

However, no need to recheck.
You have now a problem with 3V3_G3H_RTC power rail.
"L6960/61: 6 Ohms"
No idea what you did there...
 

cpuentes23

New member
My bad. L6960/61: 15.3 Ohms, rest is Ok.

L9020/21: It reads 172 Ohm, then 2.2 KO, then 0.6 KO, back to 172 Ohms, 2.2KO, 0.6 KO...
 

2informaticos

Administrator
Staff member
STOP checking in ohm scale.
Switch from diode mode to ohm scale ONLY for very low values; usually under 0.005-0.010 in diode mode.

6 or 15 ohm there is bad anyway.
You should get 0.300-0.450 in diode mode; depends of the multimeter used.
 
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