820-00165 Slow Boot & MacOS

[RaezorSharp]

I have a 820-00165 which looks like some previous liquid damage but the machine boots. Re-Installed MacOS which took more time than normal, it seems that the machine is very slow. Held down 'D' to run diag on boot but MacOS reports no issues found: Code App0000.

Also, when turning on the machine it's necessary to hold down the power button until the chime completes to get the boot going.

Eventually installed 'istat menus' and the it's showing the 'Kernel Task' @ 244%.

 

[2informaticos]

Disconnect internal SSD and try USB macOS.
If still the same, try clean ME BIOS.

 

[RaezorSharp]

Can you tell me where to get a clean ME BIOS for a 820-00165?

 

[2informaticos]

Several threads have links posted.

Just in case,

820-00165-A clean ME.rar

drive.google.com

 

[RaezorSharp]

Connected the Medusa, read the BIOS...tried to clean the ME and got an error starting the write ROM. So I loaded the file provided into Medusa and tried to write the ROM but got an 'Erase Error: 8ver' '00% W:001000'

Any suggestion as to how to get around this?
Thx

 

[2informaticos]

Do not connect charger, nor battery to MLB.
Just inject external 3V into 3V3_SUS.
I use a wire soldered to Medusa, to get this voltage.

 

[RaezorSharp]

curious as to where on the Medusa you grab the 3v from?

 

[2informaticos]

Port A connector; the one who goes to Mac board.
Second pin has 3V...

 

[RaezorSharp]

I had an issue with the A4160 EasyFlash (connector came off the board), so I tried the A4140 EasyFlash and was able to write the ROM but I'm not getting a the Apple logo to boot up anymore.

 

[2informaticos]

Did you verify Medusa ROM against Mac ROM?

 

[RaezorSharp]

Yes I did verify the Medusa ROM against Mac ROM

 

[2informaticos]

Put back the backup BIOS and see what happens...

 

[RaezorSharp]

Placed the backup BIOS back and the laptop booted up at normal speed initially.... ran the browser and youtube video and then the machine started to slow down and the kernel task when backup to very high again.

Is it possible some sensor causing this issue?

After having the machine on for about 10-15 minutes running iStat Menus....the machine suddenly turned off as well.

 

[2informaticos]

The posted BIOS should be good.
You didn't write it correctly, maybe; try it again.
What about MLB temps, especially CPU?

 

[RaezorSharp]

I'll re-try the posted BIOS, not sure what might have happened.
MLB temps, posted around 43....
Will update once I get back to the laptop..

 

[RaezorSharp]

Ok, must have had an issue with the EasyFlash A4160 connector that was defective. I was able to re-program the BIOS with the posted BIOS and it's still slow.

Attached are two screen shots

 

[2informaticos]

6.16A for BMON is strange.
Check resistance between pins 17/18 and voltage at pin 15 of U7100.

 

[RaezorSharp]

Resistence between pins 17/18 on the board is measuring 3.1 ohms
Voltage at pin 15 (CHGR_BMON) is showing only 64 mV [Note: Battery is disconnected]

 

[2informaticos]

Check U5600 area; post its voltages.

Also test the machine with 45/60W Magsafe 2 charger.

 

[RaezorSharp]

U5600 Voltages are as follows
- PP3V3_S0 - 3.31v
- CHGR_CSO_R_N - 8.57v
- CHGR_CSO_R_P - 8.57v
- BMON_IOUT - 1.8mV

I have been using a 85W Magsafe 2 charger, should I use a lower wattage?