Apple MacBook Pro A1278, MB: 820-3115-B, Auto turn on with MagSafe, white screen

SMC in this motherboard has a noted issue such as “No battery connected” or “No battery charging”
So if motherboard autostarts even with battery connected SMC seems bad.
Have you also tested voltage around U4510, checking with microscope around the chip, and checking U7770 too?

valieromarco ha scritto:SMC in this motherboard has a noted issue such as “No battery connected” or “No battery charging”
So if motherboard autostarts even with battery connected SMC seems bad.

If the SMC is suspect only for an autostart issue, I will wait with it and try to repair the HDD detection first, because I don't have it on the stock.

valieromarco ha scritto:Have you also tested voltage around U4510

The voltages to ground on U4510 are as follows (measured with connected HDD drive, machine is turned on with flashing folder on the screen):

U4510 Pin number	Net	Voltage
1	SATA_HDD_D2R_RDRIN_P	0V
2	SATA_HDD_D2R_RDRIN_N	0V
3	GND	0V
4	SATA_HDD_R2D_RDROUT_N	1,08V
5	SATA_HDD_R2D_RDROUT_P	1,08V
6	=PP1V5_S0_RDRVR	1,51V
7	SATARDRVR_EN	3,29V
8	SATARDRVR_I2C_ADDR0	0V
9	SATARDRVR_I2C_ADDR1	1,47V
10	SATARDRVR_I2C_EN_L	0V
11	SATA_HDD_R2D_RDRIN_P	0V
12	SATA_HDD_R2D_RDRIN_N	0V
13	GND	0V
14	SATA_HDD_D2R_RDROUT_N	1,19V
15	SATA_HDD_D2R_RDROUT_P	1,19V
16	=PP1V5_S0_RDRVR	1,51V
17	=SATARDRVR_I2C_SDA	3,30V
18	SATARDRVR_TEST	0V
19	=SATARDRVR_I2C_SCL	3,30V
20	SATARDRVR_REXT	0,52V

valieromarco ha scritto:checking with microscope around the chip

I checked it and I found nothing suspicious:

valieromarco ha scritto:and checking U7770 too?

The voltage to ground on pin 1 of coil L7770 is 1,51V so the chip U7770 is probably good.

I also checked the continuity between the SATA cable data pins and pins 1 of capacitors C4510, C4511, C4515, C4516. There is continuity on all four data lines - the resistances are in accordance with the values of resistors R4533, R4534, R4535, R4536. The HDD is spinning. Given this, the HDD cable is probably also good (I checked with two HDD cables).

Sorry I’m out now I can’t checking all U4510 voltages.
As for U7770 important is pin 3 enable if you have 3,3V U7770 is good

valieromarco ha scritto:As for U7770 important is pin 3 enable if you have 3,3V U7770 is good

Yes, there is 3,3V on enable pin of this chip.


I noticed another thing:
If I connect the customer's SSD drive to the USB port via SATA/USB adapter, the machine normally boots to the OS:


The machine boots to the OS with new and also with old (original) EFI dump, but as mentioned only with the customers's SSD drive connected to the USB port. The internal HDD drive is not visible under "Disc Utility".
I also try to connect another SSD drive with installed OS from MacBook Pro A1286 to the same adapter, but the machine won't boot from this disc - only flashing folder on the screen.

Any idea?

U4510 voltages are correct
I suspect a problem between U4510 and J4501 and between U4510 and PCH.
There are few resistors and capacitors, replace all capacitors, resistors only if give wrong value.
There are many HDD cables damaged better if you can use one that is working on an other machine.

Hello again!

I was waiting for spare parts. Now the situation is as follows.

- HDD cable replaced with brand new one > no changes.
- All resistors around the chip U4510 checked > all seems okay.
- I didn't replace the capacitors around the chip U4510 , because in my opinion the chip itself is more likely damaged as the capacitors.

So I replace the chip U4510 and now the machine boots to the OS from customers SSD drive connected to the internal HDD connector. It seems that everything works fine now.
The strange thing is that the machine stopped turning on automatically after connecting the MagSafe. After replacing the U4510 the machine still turned on automatically, but only few times, then all of a sudden, this error has disappeared itself. I didn't touch the motherboard at all.

For now everything seems fine, except that I still can't install the OS to another HDD.
The issue is still exactly the same as described in post #4 - the bar loads to about the 60%, then it throws a crossed circle.
I tried with connected customers SSD drive and also with another formatted HDD drive. I also tried with two different memory sticks and also with two OS - "High Sierra 10.13" and "El Capitan". The issue is always the same. I also set the date and time before running the installer form the memory stick.

Maybe someone knows where the problem might be?

matic ha scritto: I also set the date and time before running the installer form the memory stick.

Maybe someone knows where the problem might be?

What date did you set? If current, this may be the problem as the offline installer does have a limited certificates validity. You may be forced to log in to a customer's OS, disable WiFi, set date manually to 01-01-2019 and try to boot from an installer again.

With my OS bootable USB El Capitan I always set the date around September 2015, and with Sierra (no High Sierra) around January 2016.
If you can't install OS with as Vogelek23 told you, try to set date before or after as I told you
Now I think the problem is only that one.

Vogelek23 ha scritto:What date did you set? If current, this may be the problem as the offline installer does have a limited certificates validity.

Yes, I set the current date and time.

Vogelek23 ha scritto:You may be forced to log in to a customer's OS, disable WiFi, set date manually to 01-01-2019 and try to boot from an installer again.

I did it, but unfortunately it does not change anything.

valieromarco ha scritto:With my OS bootable USB El Capitan I always set the date around September 2015

I set the date to 9.9. 2015 and try with both OS (El Capitan and Sierra 10.12) but it also does not change anything.

valieromarco ha scritto:with Sierra (no High Sierra) around January 2016

I also try with the date 1.1. 2016 but it does not change anything as well (I tried with both OS).


When I click on the "Offline installer" and the loading bar appears on the screen the activity LED on Memory stick flashes for only about three seconds and then it lit constantly.

That circle means machine is not compatible with OS, please try another Os bootable disk.
Customer disk works but which Os has been installed?
If you have original bios dump try to flash back the original bios.
Make a bootable Os USB with previous Os version.

valieromarco ha scritto:That circle means machine is not compatible with OS, please try another Os bootable disk.

I tried with a third different USB Memory stick - no changes.

valieromarco ha scritto:Customer disk works but which Os has been installed?

On the customers SSD drive it is installed "El Capitan".

valieromarco ha scritto:If you have original bios dump try to flash back the original bios.

EFI reflashed with old (original) dump - no changes.

valieromarco ha scritto:Make a bootable Os USB with previous Os version.

I made a bootable USB Memory stick with OS "Yosemite 10.10" - exactly the same situation as before.
I have also change the date to 11.11. 2014 but it also changed nothing.

Pressing Command + R when booting can you install via internet ?
HDD/SSD is new or used? Try with another disk and erase it by utility disk before formatting.
HDD/SSD you want use to install OS which file system was formatted with?

valieromarco ha scritto:Pressing Command + R when booting can you install via internet ?

I don't want to change the OS on customer's SSD drive, I just want to install the OS on another HDD for the test only, so I will not try this.

valieromarco ha scritto:HDD/SSD is new or used? Try with another disk and erase it by utility disk before formatting.
HDD/SSD you want use to install OS which file system was formatted with?

I tried with two different (both used) HDD discs, bout both works okay on windows machine. Both discs formatted as shown on the pictures from the post #29.

I don't want to change the OS on customer's SSD drive, I just want to install the OS on another HDD for the test only, so I will not try this.

You can install OS from internet using your disks

Erase you disk format using Utility Disk and try to install from internet press command + R and then Install OS

Unfortunately I don't have an "Apple ID" and I don't want to create it just for this...

You can use yours because HDD is yours.
Otherwise you have to install OS using another machine because for unknown reason the system doesn’t recognize a compatible OS for the machine.