MacBook Pro A1398 -820-00163 1V on PPBUS

[huzeafa]

Good day guys

Have got an 820-00163 with no PPBUS voltage , there’s no short on the PPBUS and 2 confirmed isl replacements but same results. Have only got 1.5Von PPBUS.

initially, the isl was burnt, so was replaced and also current sensing resistors values were off , so also replaced. The two switch transistors for the isl also replaced , but still 1.5V on output.
Below are the isl measurements
Voltage
1.CHGR_AGATE=15.3V
2.CHGR_DCIN=15.7V
3.CHGR_ACIN=3.7V
4.CHGR_VFRQ=3V
5.CHGR_ICOMP=0.1V
6.CHGR_CELL=3V
7.CHGR_VCOMP=0.6V
8.CHGR_VCOMP0.6V
9.CHGR_AMON=4.5V
10.SMBUS_SMC_5_G3_SDA=3V
11.SMBUS_SMC_5_G3_SCL=3V
12.PP3V42_G3H=3V
13.CHGR_RST_L=3V
14.SMC_BC_ACOK=3V
15.CHGR_BMON=1.5V
16.CHGR_BGATE=1.5V
17.CHGR_CSO_N=1.5V
18.CHGR_CSO_P=1.5V
19.PP5V1_CHGR_VDD=5V
20.PP5V1_CHGR_VDDP=5V
21.CHGR_LGATE=0.0V
22.GRD
23.CHGR_PHASE=1.5V
24.CHGR_UGATE=1.5V
25.CHGR_BOOT=5V
26.CHGR_SGATE=5V
27.CHGR_CSI_N=15V
28.CHGR_CSI_P=15V

Diode


1.CHGR_AGATE=0.654
2.CHGR_DCIN=0.586
3.CHGR_ACIN=0.554
4.CHGR_VFRQ=0.432
5.CHGR_ICOMP=0.781
6.CHGR_CELL=0.745
7.CHGR_VCOMP=0.761
8.CHGR_VCOMP0.562
9.CHGR_AMON=0.551
10.SMBUS_SMC_5_G3_SDA=0.531
11.SMBUS_SMC_5_G3_SCL=0.532
12.PP3V42_G3H=0.356
13.CHGR_RST_L=0.531
14.SMC_BC_ACOK=0.563
15.CHGR_BMON=0.756
16.CHGR_BGATE=0.656
17.CHGR_CSO_N=0.425
18.CHGR_CSO_P=0.446
19.PP5V1_CHGR_VDD=0.356
20.PP5V1_CHGR_VDDP=0.324
21.CHGR_LGATE=0.454
22.GRD
23.CHGR_PHASE=0.432
24.CHGR_UGATE=0.832
25.CHGR_BOOT=0.545
26.CHGR_SGATE=0.675
27.CHGR_CSI_N=0.875
28.CHGR_CSI_P=0.644

 

[2informaticos]

" 9.CHGR_AMON=4.5V
------------------
15.CHGR_BMON=1.5V"
Both too high...

Post exact ohm resistance measured between pins 17/18 and 27/28.