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820-00840 no boot!!
- Thread starter phantom
- Start date
i don't know what happen: now i have 5v on both ports...ppbus_g3h is 0v (no shorted)
with battery connected, .ppbus_g3h is 1,3v
3,3 1,1 1,8 present on both controllers but unstable....like in loop
display of amp meter power off and then on in loop after 4/5 seconds
SMC_RST is 3,0v unstable
with battery connected, .ppbus_g3h is 1,3v
3,3 1,1 1,8 present on both controllers but unstable....like in loop
display of amp meter power off and then on in loop after 4/5 seconds
SMC_RST is 3,0v unstable
Last edited:
Check diode mode to ground on all big coils.
Test the board alone on the desk, only charger connected.
Inspect USB-C terminals for corrosion.
Test the board alone on the desk, only charger connected.
Inspect USB-C terminals for corrosion.
Power ciclying may be sign of a problem in a secondary power supply.
Check in diode mode all output rails from page 64.
Just in case, test in SMC bypass mode.
Remove F7000 and check C7050 voltage.
3V3_G3H gets stable voltage?
Check in diode mode all output rails from page 64.
Just in case, test in SMC bypass mode.
Remove F7000 and check C7050 voltage.
3V3_G3H gets stable voltage?
PP1V8_S0
pP1V2_S3
pP1V8_S3
pP1V8_S5g
pp5v_s5
pp3v3_s5
pp3v3_s4
pp5v_s0
pp1v_s3
pp1v2_s3
pp3v3_s0
pp1v2_s0
All ok in diode mode,
after removing f7000 (i know is a coincidence) , i have had 20v on both ports for like 5 times (removing and reinserting the cable), then again 5v....
in this moment (5v on usb with power meter that reboot itself) i have 0,3v on c7050
pp3v3_g3h is unstable
3v3_g3h is unstable
) and now i have (i hope) 20v rocksteady on both ports, but no boot
Did you resolder F7000?
Do you get 3V3_S5?
Do you get 3V3_S5?
What is CPU core voltage behavior?
It should drop to 0.65V after 10-15s, when board boots.
It should drop to 0.65V after 10-15s, when board boots.
Try at L7210/20...
The other coils on the board have the same behavior?
Test the board in SMC bypass and safe mode also.
Test the board in SMC bypass and safe mode also.
"how can i go in bypass mode?"
boards.rossmanngroup.com
HOW TO collection
I hope this "How to" collection will help our members. I will possibly modify this post in time, if updates available. Trigger SMC_ONOFF_L (PMU_ONOFF_L): It reffers to simulate power button function, when the keyboard is not connected. We need to do this when we work with the board...
boards.rossmanngroup.com