A1707 5V STUCK

[Arshad alam4659]

macbook a1707 820-00928-a no liquid damage 5v stuck i checked some voltage
PP3V3_G3H=3.4v
PPVIN_G3H_P3V3G3H=4.7v
PPDCIN_G3H=5v
PP1V8_UPC_TB_LDOD=1.79v
PP3V3_UPC_TB_LDO=3.3v
PP1V1_UPC_TA_LDO_BMC=1.1v
PPBUS_G3H=0v no shorting to ground

what should Icheck next

[mon2]

PPBUS_G3H=0v

Check both sides of the fuse on PPBUS_G3H to confirm the fuse is not blown.

What is the current draw of the 5v? Each CD3215 must be inspected and measured for their local LDO rails.

These webpages are applicable:

https://logi.wiki/index.php/CD3215_Bootup_Sequence

https://repair.wiki/w/MacBook_Pro_A1..._of_20V_repair

https://boards.rossmanngroup.com/thr...-on-usb.60302/

https://www.youtube.com/watch?v=EOtK9UWM3pk

[Arshad alam4659]

https://logi.wiki/index.php/CD3215_Bootup_Sequence
i checked this sequence

PP20V_USBC_XB_VBUS =5v
PP3V3_UPC_XB_LDO=3.3v
PP1V8_UPC_XB_LDOA=1.79v
PP1V8_UPC_XB_LDOD=1.79v
PP1V1_UPC_XB_LDO_BMC=1.1v
HV_GATE1= not checked because under the cd 3215
HV_GATE2=not checked because under the cd 3215
PPDCIN_G3H=5v
TBA_VDDA=5v
PM_EN_P3V3_G3H=5v
PP3V3_G3H=3.4v
PP1V2_S5_SMC_VDDC=1.2v
PP3V0_S5_AVREF_SMC=2.9v
SMC_RST_L=3.4v
SMBUS_SMC_4_G3H_SCL=0.131v
SMBUS_SMC_4_G3H_SDA=0.620v
USBC_XB_CC1=0v
USBC_XB_CC2=1.4v
PP20V_USBC_XB_VBUS=5v
TBA_AUX_DET=1.2v

[mon2]

Check both CD3215 as per the linked article. UB300 & UB400.

[Arshad alam4659]

Check both CD3215 as per the linked article. UB300 & UB400.

please quote me which article

[mon2]

https://logi.wiki/index.php/CD3215_Bootup_Sequence

[Arshad alam4659]

https://logi.wiki/index.php/CD3215_Bootup_Sequence

sorry for my english is not good

i changed both cd3215 ub 300 and ub 400 now board is ok but i have a question how to confirm which side cd3215 is bad all port same behaviour also all ldo ok
all chip are in sequence 9 are ok but sequence 10 (SMBUS_SMC_4_G3H_SCL= 0v)
Do I need to change them all at once?

[mon2]

Remove all power. Measure the resistance to ground on SMBUS_SMC_4_G3H_SCL.

What is the resistance in ohms?

[Arshad alam4659]

Remove all power. Measure the resistance to ground on SMBUS_SMC_4_G3H_SCL.

What is the resistance in ohms?

my board is now ok problem is solved cd3215 was bad
SMBUS_SMC_4_G3H_SCL=90k (no shorting was here)
My question is how to confirm which cd3215 is bad if all cd3215 are in the same condition I have to pick them all up and check them

[mon2]

I would suggest to remove all power -> meter in DIODE mode -> red meter probe to ground (yes ground) -> black meter probe to point to test.

Test each and every CD3215 on the board to hunt for a part with a different reading than others. Often, the diode mode measurement will reveal the defective CD3215. You can study the diode mode measurements from the websites / schematics(?) to obtain the good diode measurement ranges.

[Arshad alam4659]

I would suggest to remove all power -> meter in DIODE mode -> red meter probe to ground (yes ground) -> black meter probe to point to test.

Test each and every CD3215 on the board to hunt for a part with a different reading than others. Often, the diode mode measurement will reveal the defective CD3215. You can study the diode mode measurements from the websites / schematics(?) to obtain the good diode measurement ranges.

thanks for help