A1990 820-010-41-A no power

Hi,
I have an A1990 820-010-41-A that came to me two weeks ago with no power, that had one CD315 burnt. I replaced the CD3215, and the mac started working again, with no other problem.

Then, after a few days, the client reported that the mac stoped charging the battery, and now it doesn't power on at all. The metter only shows 5V, on all ports, and the ampmeter doesn't reboot on any port (steady 5V on all ports).

Can you help?
 
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HI,
I didn't check the power on sequence, but on the fuses I get 5V.
I thought that maybe it was already a known problem... I'll measure them
 

2informaticos

Administrator
Staff member
There could be several reasons to get it stuck in 5V input.
We need some readings from the board...
 
You're right. Sorry

F3000 = 5V both pins

I stopped here (PPBUS_G3H) because i don't understand those measures, and don't know exactly what to do next :

On two ports I get:
PPBUS_G3H = oscillates between 7 and 11V

And on the other 2 ports I get
PPBUS_G3H = = 3.2V

I get different values on several rails, depending on witch port i connect the power
 
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2informaticos

Administrator
Staff member
If you get different behaviour, depending which USB-C port is powered on, then you have a problem on the USB-C area.
Try to reflow, or change again that CD3215 chip.
 
Yes, still differente values deppending on the port powered on.

PPBUS_G3H has 3.1V or 7~11 deppending on the port connected
 
Hi,
On R7020 I have 0V on all 4 pads.
But now, the metter reboots on 3 ports. I suppose that the CD3215 controlling the port that has steady 5V, is the one causing the problem. Correct? How can I be sure?
 
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2informaticos

Administrator
Staff member
In theory that port has problems.
But you should get voltage at R7020.
U7000 requires at least 5V input.
Check diode mode to ground there.
 
Diode on R7020 is OK (0,507V) on all pads.
when connected on the ports that reboots the metter, i get 0.3 ~0.5V on R7020 PPDCIN_G3H_CHGR
 
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Yes, on R7071, the values are the same (diode and voltage), with the difference that the voltage oscilates a bit higher (0.3 ~0.9V), and one time it reached (very, very quickly 2V and then continuated to oscilate from 0.3 to 0.7V))
 

2informaticos

Administrator
Staff member
Then you have a common problem for all USB-C ports; at least one should get 5V at R7020.
Check all input fuses, near CD3215 chips.
 
I didn't measured R7020 with all USB-C ports. Only with one that is rebooting the metter. Shall i measure R7020 on all ports connected? On the fuses i get 0~5V (rebooting) and steady 5V on the steady port.
 
The measures are the same on all ports, except when connected to the steady 5V port. On that one, i get 0V (0.0003V)on all pads of R7020
 
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