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PPBUS_G3H missing on a1932
- Thread starter Leroy
- Start date
Check diode mode at 3V3_G3H_RTC please.
Unfortunatelly this board doesn't have a fuse to separate PPBUS_G3H, like other models.
Is more difficult to deal with it.
Post U7000 basic voltages: P_IN, AUX_DET, SMC_RST_IN, VDDA/P, EN_MVR, AUX_OK, A/BMON.
Use proper points for test; find corresponding lines on the surrounding components.
Unfortunatelly this board doesn't have a fuse to separate PPBUS_G3H, like other models.
Is more difficult to deal with it.
Post U7000 basic voltages: P_IN, AUX_DET, SMC_RST_IN, VDDA/P, EN_MVR, AUX_OK, A/BMON.
Use proper points for test; find corresponding lines on the surrounding components.
The readings look good.
Just in case, check resistance over C7020/23 (ohm scale).
The only way to somehow isolate PPBUS_G3H, is to remove Isense resistors: R5400/10/20/30 and R5600/10.
Some of them may not be placed.
In such case should cut off the trace between corresponding pads (in the middle).
Be aware, do not go too much down the board!
Before salvaging PPBUS_G3H rail, I recommend to test its voltage with battery connected.
Preferible holding some charge on it...
Just in case, check resistance over C7020/23 (ohm scale).
The only way to somehow isolate PPBUS_G3H, is to remove Isense resistors: R5400/10/20/30 and R5600/10.
Some of them may not be placed.
In such case should cut off the trace between corresponding pads (in the middle).
Be aware, do not go too much down the board!
Before salvaging PPBUS_G3H rail, I recommend to test its voltage with battery connected.
Preferible holding some charge on it...
So PPBUS_G3H doesn't go over 1.2V?
"the probes on either sides off the capacitor?"
Yes.
In fact you are measuring the sum of the 3 corresponding resistors!
"the probes on either sides off the capacitor?"
Yes.
In fact you are measuring the sum of the 3 corresponding resistors!
Check R7021/2 and their traces to R7020.
R7021 309.8 ohm and on both sides 4.1v
R7022 12.0 ohm CHGR_CSIR_N 4.5v CHGR_CSI_N 5.1v
r7020 PPDCIN_G3H_CHGR_AMON 5.180v, PPDCIN_G3H 5.180v, CHGR_CSI_N 5.180v, CHGR_CSI_P 4.123v
I noticed when connect to the other usb-c port the numbers jump around more. For example r7021 jumps from 4.1v to 3.8v to 2.9v and back to 4.1v.
3V3_G3H_RTC jumps now from 3.2v to 2.0v and back
PPBUS_G3H 5.9v to 6.1v to 6.8v. with power on the other usb-c 5.3v-5.8v-6.4v
R7022 12.0 ohm CHGR_CSIR_N 4.5v CHGR_CSI_N 5.1v
r7020 PPDCIN_G3H_CHGR_AMON 5.180v, PPDCIN_G3H 5.180v, CHGR_CSI_N 5.180v, CHGR_CSI_P 4.123v
I noticed when connect to the other usb-c port the numbers jump around more. For example r7021 jumps from 4.1v to 3.8v to 2.9v and back to 4.1v.
3V3_G3H_RTC jumps now from 3.2v to 2.0v and back
PPBUS_G3H 5.9v to 6.1v to 6.8v. with power on the other usb-c 5.3v-5.8v-6.4v
Last edited:
"I noticed when connect to the other usb-c port the numbers jump around more. For example r7021 jumps from 4.1 to 3.8 to 2.9 and back to 4.1."
What???
Are you checking ohm scale (and diode mode) with power on the board???
What???
Are you checking ohm scale (and diode mode) with power on the board???
You didn't reply to my question!
"R7021 309.8 ohm
R7022 12.0 ohm"
Are these readings with power applied to the board???
If yes (I hope NOT), don't do it again.
As per schematic, BOTH mentioned resistors have 1 ohm.
2-3 ohm readings is normal then; on BOTH!
"R7021 309.8 ohm
R7022 12.0 ohm"
Are these readings with power applied to the board???
If yes (I hope NOT), don't do it again.
As per schematic, BOTH mentioned resistors have 1 ohm.
2-3 ohm readings is normal then; on BOTH!
So none of them has correct value; replace them.
What is actual PPBUS_G3H voltage?
Check it with both charger and battery connected.
Board tries to start with battery connected?