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A1708 820-0840-A no power
- Thread starter hgoncalves
- Start date
hgoncalves
Active member
They look clean and F3000 has 2.5K ohm of resistance to ground
Check diode mode to ground on the CC1/2 pins of the CD3215 chips.
hgoncalves
Active member
It looks that U3100 is shorted.
Diode readings:
U3100
CC1=0.041
CC2=0.122
U3200:
CC1=0.545
CC2=0.550
Diode readings:
U3100
CC1=0.041
CC2=0.122
U3200:
CC1=0.545
CC2=0.550
Two bad readings point to bad U3100...
hgoncalves
Active member
Hi,
I've replaced U3100 and now i get 5V on one usb-c port and 5V on F3000.
However, on the other usb-c port i get black ampmeter, and 0V on F3010, but diode readings on CC1/2 of U3200 are the same as U3100 (good)
I've replaced U3100 and now i get 5V on one usb-c port and 5V on F3000.
However, on the other usb-c port i get black ampmeter, and 0V on F3010, but diode readings on CC1/2 of U3200 are the same as U3100 (good)
hgoncalves
Active member
Hi,
It seams that I have a short in PP3V3_UPC_XB_LDO.
C3208 has 0.0006 in diode reading.
It seams that I have a short in PP3V3_UPC_XB_LDO.
C3208 has 0.0006 in diode reading.
Very likely bad U3200.
You should remove C3208 and test again.
Be aware, PP3V3_UPC_XB_LDO splits into more rails; look at pages 28 and 69.
You should remove C3208 and test again.
Be aware, PP3V3_UPC_XB_LDO splits into more rails; look at pages 28 and 69.
hgoncalves
Active member
Hi,
After removing U3200 the PP3V3_UPC_XB_LDO short is gone, but afetr I replaced U3200, now i get 5.15V on both usb-c ports
After removing U3200 the PP3V3_UPC_XB_LDO short is gone, but afetr I replaced U3200, now i get 5.15V on both usb-c ports
Do you get correct LDO rails for CD3215 chips now?
Check in voltage and diode mode.
Any other voltages appear on the logic board?
What happens if you connect known good battery, with some charge?
Check in voltage and diode mode.
Any other voltages appear on the logic board?
What happens if you connect known good battery, with some charge?
Last edited:
hgoncalves
Active member
OK,
the first cd3215 (U3100) was bad (don't understant why, because the readings were the same as the U3200). After replacing it, it started to work again.
TKS
the first cd3215 (U3100) was bad (don't understant why, because the readings were the same as the U3200). After replacing it, it started to work again.
TKS