Do you have access to chinafix.com? I tried searching for PPVCCEDRAM_S0_CPU and I found a promising discussion that I'm unable to read as a new member :/
[url]https://www.chinafix.com/thread-1265122-1-1.html[/url]https://Do you have access to chinaf...1-1.html[/url]
Ryan.man
New Member
Last Activity: 03-16-2025, 08:23 PM
Joined: 02-03-2025
Location: Belo Horizonte
-
Thanks for the tip, the first stage (that generates the main power rails) is working nice. I'll check later for some of the intermediate signals at next stages. I already know PPVCCSA_S0_CPU and PPVCC_S0_CPU both look ok, and that PPVCCGT_S0_CPU is always 0, but I read somewhere that this last signal will only activate when there is demand for graphics.
I'm still suspecting my eDRAM is not being powered up. Is there any other diagram like those you've sent me that shows [I]PPVCCEDRAM_S0_CPU[/I] being generated?Thanks for the tip, the first stage (that generates the main power rails)Leave a comment:
-
So, I had some time to check a lot of signals and I have still not give up trying to find the problem here, although I'm getting less hopeful as I dig through.
I checked the voltages of all power lines listed on the "power aliases" page of the 820-00923 schematics and all of them seen fine:
PPBUS_G3H 13.02
PPBUS_HS_CPU 13.02
PPBUS_HS_OTH5V 13.02
PPBUS_HS_OTH3V3 13.02
PPBUS_S4_HS_TPAD 13.02
PPDCIN_G3H 20
PP3V3_G3H 3.3
PP3V3_G3H_SMC_ISNS 3.3
PPVCCIO_S0_CPU 0.956
PPVCCPRIMCORE_SUS_PCH 1.00
...Leave a comment:
-
Doesn't the board have a circuit to reduce cpu clock when its temperature is too high? Well, even if it has, I can't be sure it is working correctly...
Anyway, good thing that I was turning it off right after measuring, then. I don't think cpu temperature went over 70 degress celsius because I was still able to put a finger on the heatsink without burning myself.
The PPBUS_G3H went normal when I measured it with the board disconnected from everything and powered only by the original charger.
Before, when I got 10.5V, it was powered by the battery and with...Leave a comment:
-
I did look at the suggested reading.
[B]=> Check for 0.4 V in diode mode on SMBUS_SMC_5_G3H_SDA and SMBUS_SMC_5_G3H_SCL (red probe on GND)[/B]
My multimeter gave me 0.445V for both lines. I guess this is ok, right?
The other suggestions on that wiki gave normal readings.I did look at the suggested reading.
[B]=> Check for 0.4 V in diode mode on SMBUS_SMC_5_G3H_SDA and SMBUS_SMC_5_G3H_SCL (red probe on GND)[/B]
My multimeter gave me 0.445V for both lines. I guess this is ok, right?
The other suggestions on that...Leave a comment:
-
I don't have the USB-C Meter, I'll buy one. I won't be able to work on this till Monday, so next time I'll probably have it already. I still did not take the F7000 fuse out.
The measurements I did before were taken with the logic board still connected to the whole case (including the antenna and the screen).
Now I removed the logic board entirely and I got the following values when turning it on by plugging the [U]original charger [/U]to a usb-c port:
[B](F7000 is still on the board!)[/B]
[TABLE="border: 1, cellpadding: 1, width: 500"]
...Leave a comment:
-
Oh, I should have mentioned before: I measured the 10.5V with the macbook turned on. Now I measured it while macbook was shut down and it was 11.64V.
I just measured the resistance without a power source (battery disconnected). It looks like it stabilized around 190k ohms, after capacitance transient is gone.Leave a comment:
-
Hey, thank you for your prompt response!
I am a bit in a hurry with daily activities, I did not have much time delving into schematics, but I was able to measure what you asked for. It is giving me 10.5V on both sides. Not sure if this is too low, as it seems it should be a bit over 12V.
Could you give me some tips on which components/power lines/data lines I should check first to be sure it is being correctly energized? I greatly appreciate your input!
Leave a comment:
-
Macbook 2017 with touchbar (A1706) won't turn on after removing the screen
Hello everybody! Posting this in hopes somebody has some expertise that leads to a clear path of troubleshooting that saves me a lot of time!
My macbook has the flex cable problem, the one that prevents the screen turning on. Ive been dealing with this for the last 3 years. Last year it went dead and I managed to fix it following youtube tutorials. But my fix wasnt the best, the problem returned a month later. This week, it went dead again. I again tried to fix it.
This time the original cable broke too close to the screen, it can't be fixed without tearing the screen...
No activity results to display
Leave a comment: