820-01987 No power

[Zebulon]

So I guess that means I would have to remove the metal cover around that area?

I said to check AWAKE and SLPS2R on the small coils around U7800, as refference.
Using boardview, may find another points where to test them.

Reflash U4770 and try again DFU.
Don't forget to make backup first.

 

[2informaticos]

Can't you find another components, out of the shield cover, connected to the same coils?
Maybe on the other side of the board, under U7800, or T2.
If not, then remove the shield cover...

 

[Zebulon]

I will give that a try! Thanks for all the help. I'll let you know know the results!

Can't you find another components, out of the shield cover, connected to the same coils?
Maybe on the other side of the board, under U7800, or T2.
If not, then remove the shield cover...

 

[Zebulon]

So here are all the readings for the coils around U7800 ...

L7810 = 0.456
L7812 = 0.047
L7809 = 0.045
L7815 = 0.278
L7816 = 0.107
L7813 = 0.428
L7819 = 0.304
L7822 = 0.207
L7823 = 0.416
L7824 = 0.384

 

[2informaticos]

As diode mode readings, doesn't look bad.
You've been asked to check for voltage!

 

[Zebulon]

Oh, ok, I will do that as soon as I can, then post those results! Thanks again!

As diode mode readings, doesn't look bad.
You've been asked to check for voltage!

 

[2informaticos]

Please, don't quote an entire post, visible few centimeters above...

 

[Zebulon]

Sorry for the quote. I was not able to get to this for a long time, but anyway, here are the voltages. Where I write a dash it's because the voltage is bouncing from zero to that voltage and back to zero...

L7810 = 0.0v - 0.84v
L7812 = 0.0v - 0.82v
L7809 = 0.0v - 0.75v
L7815 = 0.0v - 1.1v
L7816 = 0.0v - 0.9v
L7813 = 0.0v - 1.84v
L7819 = 0.0v
L7822 = 0.0v
L7823 = 0.0v
L7824 = 0.0v

 

[2informaticos]

"Reflash U4770 and try again DFU.
Don't forget to make backup first."
Tried that?

You should try first reflashing U2890 ..

 

[Zebulon]

I will try this thanks! Will it be a problem to use a 13" M1 MacBook Pro running the latest MacOS and Apple Configurator 2?

 

[2informaticos]

It should work...

 

[Zebulon]

I realized the chip is far to small for my CH341 is there an adapter I can get to be able to use this programer or will I have to get a different programer?

 

[2informaticos]

Make time and read more threads on the forum, not just yours.
You can't imagine how much useful information you will find...

820-00850-A - Tries to turn on and restarts

I do have a CH341A Linkj ->...

boards.rossmanngroup.com