smiba
New member
Hey everyone
This device came in with the regular PP3V3R3V0_AON short to ground, I first suspected U7600 so I removed it but the short did not go away.
After lifting up and soldering back 2 other chips (I think around U4450) I finally found the suspect on the other side of the board: U4700.
After replacing U4700 and placing on a new U7600 the board has AON and PPBUS_G3H as well as the other G3H voltages (PPBUS_G3H, PPVRTC_G3H, PP5V_G3H_LDO, PPVBUS_E85, PPDCIN_G3H).
It did not go further then S5. I tried powering on the device by shorting SMC_ONOFF_L to ground as I was not sure if this device powers on by default. I used R5115 which is a little pad almost underneath the battery connector (Thats the right one, right?)
Just to confirm I was not just being dumb I placed the machine back together but with no luck, the power button didn't boot it ether.
After taking the device apart again PP3V3R3V0_AON was shorted again, which I directly traced back to the replaced U4700. I replaced it once again (why do they die so easily?) with a new one and we're back at no S4. (But we do have S5)
PPBUS_G3H: OK
PPVRTC_G3H: 3.28V
PP5V_G3H_LDO: 4.98V
PPVBUS_E85: OK
PPDCIN_G3H: OK
PP3V3_S5: 3.28V
PP3V3_S4: 0V
PP5V_S4: 0V
One weird thing I have to mention is that at some point PP5V_S0 was steady at about 4.2V (not just stray capacitance as it did go to 0V when disconnecting the power) even though all the S0/S3/S4 voltages were not there. Not sure if its important but it was definitely odd.
Where to look? Thanks!
This device came in with the regular PP3V3R3V0_AON short to ground, I first suspected U7600 so I removed it but the short did not go away.
After lifting up and soldering back 2 other chips (I think around U4450) I finally found the suspect on the other side of the board: U4700.
After replacing U4700 and placing on a new U7600 the board has AON and PPBUS_G3H as well as the other G3H voltages (PPBUS_G3H, PPVRTC_G3H, PP5V_G3H_LDO, PPVBUS_E85, PPDCIN_G3H).
It did not go further then S5. I tried powering on the device by shorting SMC_ONOFF_L to ground as I was not sure if this device powers on by default. I used R5115 which is a little pad almost underneath the battery connector (Thats the right one, right?)
Just to confirm I was not just being dumb I placed the machine back together but with no luck, the power button didn't boot it ether.
After taking the device apart again PP3V3R3V0_AON was shorted again, which I directly traced back to the replaced U4700. I replaced it once again (why do they die so easily?) with a new one and we're back at no S4. (But we do have S5)
PPBUS_G3H: OK
PPVRTC_G3H: 3.28V
PP5V_G3H_LDO: 4.98V
PPVBUS_E85: OK
PPDCIN_G3H: OK
PP3V3_S5: 3.28V
PP3V3_S4: 0V
PP5V_S4: 0V
One weird thing I have to mention is that at some point PP5V_S0 was steady at about 4.2V (not just stray capacitance as it did go to 0V when disconnecting the power) even though all the S0/S3/S4 voltages were not there. Not sure if its important but it was definitely odd.
Where to look? Thanks!