EsteTron
Member
MacBook Air came in for no power. No signs of liquid damage. All G3H and S5 rails present. Hooked up to DCPS and drawing 0.027Amps. Pulled board out and discovered the 25MHZ Clock Crystal Y1905 had exploded. Replaced Y1905 and Replaced u1900 RTC Clock since it was next to the clock crystal. Still missing PM_SLP_S4-L.
U1900 power:
Pin13: PP3v42_G3H = 3.44V
Pin2: PP3v3_s5 = 3.3v
Pin5: PP3V3_S5RS3RS0_SYSCLKGEN = 3.3v
Started looking around board and discovered another 24MHZ Crystal Y1915 (PCH Crystal) was starting to bulge gunk out of the side of it.Replaced it since it looked ready to die. Still now luck. Strange to see two clocks crystal dying.
After poking measurements around the board, the only measurement that really stood out to me PCH INTRUDER L reading 3.0v instead of 3.3v. When I measured PCH_INTRUDER_L for the first time, I got a fanspin for about 5 seconds, and then nothing. Is it possible that the PCH is pulling down voltage on PCH_INTRUDER_L? Just to make sure there was no junk hiding underneath PCH, I gave USC, but to no avail.
The part that is getting me is that it did briefly power on when I measured R1301 PCH_INTRUDER_L.
U1900 power:
Pin13: PP3v42_G3H = 3.44V
Pin2: PP3v3_s5 = 3.3v
Pin5: PP3V3_S5RS3RS0_SYSCLKGEN = 3.3v
Started looking around board and discovered another 24MHZ Crystal Y1915 (PCH Crystal) was starting to bulge gunk out of the side of it.Replaced it since it looked ready to die. Still now luck. Strange to see two clocks crystal dying.
After poking measurements around the board, the only measurement that really stood out to me PCH INTRUDER L reading 3.0v instead of 3.3v. When I measured PCH_INTRUDER_L for the first time, I got a fanspin for about 5 seconds, and then nothing. Is it possible that the PCH is pulling down voltage on PCH_INTRUDER_L? Just to make sure there was no junk hiding underneath PCH, I gave USC, but to no avail.
The part that is getting me is that it did briefly power on when I measured R1301 PCH_INTRUDER_L.