820-00239-A 5V on charger, PP3V3_G3H is 1v

Hi. I have an A1706 that gets only 5v 200mA on all four usb-c ports. Won't power on obviously.

PP3V3_G3H shows 1.2v no matter which usbc I use. The ports looked funky. I took both out and connected a brand new port. Made no difference.

Diode mode to ground shows 0.331 on PP3V3-G3H
 

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Avoid touching pins of such kind of chip!
Use surrounding components as test points.

"U6903:10 PM_EN_P3V3_G3H 0.06v"
Enable signal doesn't come from U7000.
Post U7000 basic voltages; P_IN, VDDA/P, AUX_DET, SMC_RST*, AUX_OK.
Check diode mode to ground at F7000.
 
Ah, okay. Very helpful. Thank you.
Did the voltage again with test pins.

U6903:1 P3V3G3H_VBST 5.65v
U6903:2 PPVIN_G3H_P3V3G3H 4.66v
U6903:3 P3V3G3H_LX 1.04v
U6903:4 GND
U6903:5 P3V3G3H_AGND 0v
U6903:6
U6903:7 P3V3G3H_AGND 0v
U6903:8 P3V3G3H_BIAS 4.65v
U6903:9 P3V3G3H_FB 0.33v
U6903:10 PM_EN_P3V3_G3H 4.95v
 

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"U6903:10 PM_EN_P3V3_G3H 4.95v"
So enable signal is present indeed.
Be sure to post accurate information ALWAYS.

Check R6908 and feedback resistors R6910-13.
If good, change C6907.
 

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Must check the resistors in ohm scale.
Onboard measurments will not match the exact value; remove and check them out.
 
Ah okay.

These are the measurements I got from the pads.

R6908:1 P3V3G3H_VBST_R 5.67v
R6908:2 P3V3G3H_VBST 5.67v
P3V3G3H_VBST diode mode 0.579
P3V3G3H_VBST_R diode mode 0.579

R6910:1 P3V3G3H_FB 0.33v
R6910:2 P3V3G3H_FB_R 0.94v
P3V3G3H_FB diode mode 0.560
P3V3G3H_FB_R diode mode 0.333

R6911:1 P3V3G3H_FB 0.33v
R6911:2 P3V3G3H_FB_RC 0v
P3V3G3H_FB_RC diode mode 0.494

R6912:1 PP3V3_G3H_REG_R 0.33v
R6911:2 P3V3G3H_FB_R 0.94v
PP3V3_G3H_REG_R diode mode 0.328

R6913:1 P3V3G3H_FB_RC 0v
R6913:2 P3V3G3H_AGND 0v
P3V3G3H_AGND diode mode 0.0
 

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I said to check the resistors value in ohm scale.
Nothing to check on the board to ground.
"remove and check them out."
 
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