820-00840 stuck at 5v on port a, 5v loop on port b

[phantomEVO]

Hi guys i have an 820-00840 that not boot... (stuck at 5v)

here there is the history of previous techician (i can't say if it is 100% true)

macbook dead

found a short with thermal camera on c3000

caps removed (not replaced)

tried to charge -> smoke

found u3100 burnt

changed, no luck

changed u3200 no luck

rechanged u3200 with the original one. No luck

now i have this laptop.

i have discovered that i have 5v @0.20a STUCK on usb port connected on 3100

i have 5v@0.40a in bootloop on usb connected on 3200...

any help?


Here ppdcin g3h chgr behaviour (if i connect power supply on the port that loops)

No voltage it i connect in the other port

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Update: changed but usb-controller

Now i have 20v stuck at 0,13amp

Using Thermal camera i have u7800 super hot and one usb-c controller hot

https://uploadnow.io/files/5Ppwgwk

I have checked for shorts around and under u7800 with no luck



I have pp3v3 ldo 3v
I have ppbus pmic 13v
I have pp1v25_ref 1,3v

But pp5v ldo stuck at 2,7v This Line is not shorted

[SMDFlea]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Using Thermal camera i have u7800 super hot and one usb-c controller hot

https://uploadnow.io/files/5Ppwgwk

Post your images to badcaps as an attachment please, the link goes to a login screen,it might be working ok for you but nobody else can see anything.

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

It is a video!

Can’t you see it?

https://youtube.com/shorts/Y6c0LVh7DPw?feature=share

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Check Now

https://uploadnow.io/s/46288f1b-0bf1...0-eeb33a19aa0d

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Ok i have replaced u7800 Now i have po5vldo… u7800 is not super hot anymore…(but hot together with u7100)

Now is super hot u3900 and a little bit cpu…

This is the amp meter

https://uploadnow.io/f/nJDYmsx

I have Nothing on display, no caps lock no fan spinning

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Changed u3900 still the same…


Please help!

[mon2]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

Try to test with a bootable USB media and check if the LED on the memory stick blinks during the boot process or not.

Could be a defective CPU but the climbing current draw in your posted video may show some hope that the logic board is booting.

https://boards.rossmanngroup.com/thr...no-post.50188/

[phantomEVO]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

But i have not fan spinning or sound, i have not video and a chip super hot…😕

[mon2]

Re: 820-00840 stuck at 5v on port a, 5v loop on port b

U3900 is linked to the camera assembly.

Disconnect the camera cable and attempt to boot up again.