So my MacBook Air 13" (A1466) died suddenly, just wouldn't turn on, this was like a day after having it charged to 100% and only it sleeping since, then it just would not turn on, no orange/green light, etc. The board is 820-3437-B.
First thing I tested and noticed was that PP3V42 was missing, I then checked and it was shorted to ground so I removed L7095 and tested to see if it was system side, which it was. After injecting 3.3v the SMC started to warm up (around 40'C before I removed the voltage) so I'm guessing this means the SMC is dead?
I'm happy to attempt to replace it etc, but I don't want to do that if the next one just dies, because while I didn't test the voltage on PP3V42G3H_SW because I was in diode mode, I did go back and check it and noticed it was at 15.2v not 3.42, I've found other threads reporting the voltages of the chip for that supply and SW is indeed meant to be 3.42, but is the voltage higher because I have L7095 off the board and the circuit isn't complete, or is something wrong with U7090 and it sent too much voltage onto PP3V42_G3H killing the SMC, and possibly some other stuff?
From what I can see PP3V42G3H_FB should be ~1.3v but mine is 0.54 and PP3V42G3H_BOOST should be ~0.06v but mine is 13.3v.
As I said if this is just due to L7095 being missing and feedback not working correctly or something like that then all good, just checking before I send 15v to a new SMC. I mostly want someone to tell me a voltage injection onto PP3V42_G3H making the SMC 40 degree celsius means its dead and removing the SMC to see if ground goes away won't be pointless and annoying.
Thanks!
First thing I tested and noticed was that PP3V42 was missing, I then checked and it was shorted to ground so I removed L7095 and tested to see if it was system side, which it was. After injecting 3.3v the SMC started to warm up (around 40'C before I removed the voltage) so I'm guessing this means the SMC is dead?
I'm happy to attempt to replace it etc, but I don't want to do that if the next one just dies, because while I didn't test the voltage on PP3V42G3H_SW because I was in diode mode, I did go back and check it and noticed it was at 15.2v not 3.42, I've found other threads reporting the voltages of the chip for that supply and SW is indeed meant to be 3.42, but is the voltage higher because I have L7095 off the board and the circuit isn't complete, or is something wrong with U7090 and it sent too much voltage onto PP3V42_G3H killing the SMC, and possibly some other stuff?
From what I can see PP3V42G3H_FB should be ~1.3v but mine is 0.54 and PP3V42G3H_BOOST should be ~0.06v but mine is 13.3v.
As I said if this is just due to L7095 being missing and feedback not working correctly or something like that then all good, just checking before I send 15v to a new SMC. I mostly want someone to tell me a voltage injection onto PP3V42_G3H making the SMC 40 degree celsius means its dead and removing the SMC to see if ground goes away won't be pointless and annoying.
Thanks!
