Hi. Stuck on this one and seeking advice on whether we are facing a dead PCH.
Macbook AIR came in dead - has been to multiple repair shops, each stating to buy another computer.
Found some corrosion around the SMC (Lattice FPGA). Fixed up the missing 100k pull-up and another 0 ohm resistor @ 0201 footprint.
After the above repair, the logic board booted fine but was getting rather warm according to one of the techs. Left it on overnight and this morning is dead.
No shorts on the board. MAGSAFE (original) light is green / orange - if the battery is not docked. Have tested with and without the battery no fan spin.
Attempted the logic board ON / OFF with tweezers.
PP3V42_G3H = +3V41
PPBUS_G3H = +8v5
R7552 is 0 ohms
S5_PWR_EN = 0v
R8140 = 98 ohms
Homing in on U7501 - the 3v3 rail is present but 5v0 is not being enabled (P5VS4RS3_EN = 0 volts).
The following website & webpage are gold:
https://www.it-tech.com.au/mac-q-a/pm-slp-s4-l-timing/
Step # 4 is not a match in this checklist.
If PCH_INTVRMEN = 3v0 (not 3v3) yet the PU resistor R1302 is ok to +3v3, is the PCH dead ?
We have recently brought in BGA rework tools that can support PCH & CPU replacement but not ready to uncrate it yet. Soon but not yet.
Welcome advice on the PCH / repair advice. Thanks.
Macbook AIR came in dead - has been to multiple repair shops, each stating to buy another computer.
Found some corrosion around the SMC (Lattice FPGA). Fixed up the missing 100k pull-up and another 0 ohm resistor @ 0201 footprint.
After the above repair, the logic board booted fine but was getting rather warm according to one of the techs. Left it on overnight and this morning is dead.
No shorts on the board. MAGSAFE (original) light is green / orange - if the battery is not docked. Have tested with and without the battery no fan spin.
Attempted the logic board ON / OFF with tweezers.
PP3V42_G3H = +3V41
PPBUS_G3H = +8v5
R7552 is 0 ohms
S5_PWR_EN = 0v
R8140 = 98 ohms
Homing in on U7501 - the 3v3 rail is present but 5v0 is not being enabled (P5VS4RS3_EN = 0 volts).
The following website & webpage are gold:
https://www.it-tech.com.au/mac-q-a/pm-slp-s4-l-timing/
Step # 4 is not a match in this checklist.
If PCH_INTVRMEN = 3v0 (not 3v3) yet the PU resistor R1302 is ok to +3v3, is the PCH dead ?
We have recently brought in BGA rework tools that can support PCH & CPU replacement but not ready to uncrate it yet. Soon but not yet.
Welcome advice on the PCH / repair advice. Thanks.
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