kjchatman1
Member
the ppbus is 12.4v for a split second then it drops to 5v and continues to drop dramatically down to 1.7v. the amp meter stays at 20v 0.000a
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820-02890-a 20v present but no ppbus
- Thread starter kjchatman1
- Start date
"smbus_batt_scl/sda is .222v"
Is that voltage reading (power applied to board), or diode mode reading (no power)?
BTW, do not write end "V" after diode mode readings...
Is that voltage reading (power applied to board), or diode mode reading (no power)?
BTW, do not write end "V" after diode mode readings...
Last edited:
kjchatman1
Member
that's voltage reading
If PPBUS_AON is not maintained, you can't measure any other voltage on the board.
Remove F5200/1 and check if C5250 voltage is stable.
Remove F5200/1 and check if C5250 voltage is stable.
kjchatman1
Member
the 12 volts is stable with the fuses removed
Looks like you have problems with a secondary power supply.
Start checking all of them in diode mode and voltage pulse on outputs.
Start checking all of them in diode mode and voltage pulse on outputs.
kjchatman1
Member
how is it that 20v shows on the amp meter even thought 3v8_aon isn't there to power the pmu?
Connect another charger directly (without USB-C meter) and measure R5220 voltage.