smiba
New member
Hi,
I have a 820-3330-B here that came in with no green light on the charger and a PPBUS_G3H of 0V.
I replaced U7000 from a donor board and this brought back the green light (I also restored pin 11 as it was gone from the board). It still woudn't boot since PPBUS_G3H was way below 12V so I was under the impression that maybe it wasn't solidly soldered on. I heated it up again but this time while gently pressing down to make sure all the pins make good contact. This actually made the system boot again properly, but was rather unstable (Would power off after a few minutes of using).
After this I decided to get U7000 from another donor board because these boards come from who knows were. With this chip soldered on the system wouldn't boot and PPBUS_G3H was once again too low.
So I just bought a spool of these chips because they're not that expensive, however a new chip didn't resolve the issue either, PPBUS_G3H was still at 1.18V. The issue is probably with the circuit around it, not with the chip itself.
PPBUS_G3H is also not shorted to ground, removing the fuses still keeps PPBUS_G3H on almost the same voltage of 1.18V
Voltages:
(Using a original apple 85W charger.)
PP3V42_G3H = 3.43V (Pin 12/VHST on U7000)
PPBUS_G3H = 1.18V
PP5V1_CHGR_VDD = 5.4V (VDD & VDDP on U7000)
PPDCIN_S5_CHOP = 18.42V
CHGR_ACIN = 4.46V (Pin 3/ACIN on U7000)
Thanks in advance for the help again
I have a 820-3330-B here that came in with no green light on the charger and a PPBUS_G3H of 0V.
I replaced U7000 from a donor board and this brought back the green light (I also restored pin 11 as it was gone from the board). It still woudn't boot since PPBUS_G3H was way below 12V so I was under the impression that maybe it wasn't solidly soldered on. I heated it up again but this time while gently pressing down to make sure all the pins make good contact. This actually made the system boot again properly, but was rather unstable (Would power off after a few minutes of using).
After this I decided to get U7000 from another donor board because these boards come from who knows were. With this chip soldered on the system wouldn't boot and PPBUS_G3H was once again too low.
So I just bought a spool of these chips because they're not that expensive, however a new chip didn't resolve the issue either, PPBUS_G3H was still at 1.18V. The issue is probably with the circuit around it, not with the chip itself.
PPBUS_G3H is also not shorted to ground, removing the fuses still keeps PPBUS_G3H on almost the same voltage of 1.18V
Voltages:
(Using a original apple 85W charger.)
PP3V42_G3H = 3.43V (Pin 12/VHST on U7000)
PPBUS_G3H = 1.18V
PP5V1_CHGR_VDD = 5.4V (VDD & VDDP on U7000)
PPDCIN_S5_CHOP = 18.42V
CHGR_ACIN = 4.46V (Pin 3/ACIN on U7000)
Thanks in advance for the help again