Macbook A2289 820-01987

[2informaticos]

0.700 is low reading for you (in diode mode)?
Why don't compare with other good board?

You can try to write another chip; to discard issues with original one.

 

[sourcensolutionsonline@gm]

I will definitely try that, it was indeed 0.070 I mean to write my apologies.

 

[sourcensolutionsonline@gm]

I was looking around but could not find A2289 donor boards , I have a A1989 donor board , can i harvest that U2890 from it ? I dont know if they are the same , Please advice Thank you .

 

[2informaticos]

TBT ROM is the same, just make a backup first; you may need that info in the future.

 

[sourcensolutionsonline@gm]

Will do Thank you

 

[sourcensolutionsonline@gm]

I harvested the TBT ROM from a A1989 i backed up the data of the 2289 and write it to the A1989 and reinstalled it , the result did not change, i am still stuck at 5V at my USB meter .

 

[2informaticos]

Did you write corresponding A2289 file into the new chip?

 

[sourcensolutionsonline@gm]

Yes correct , that was exactly what i did.

 

[2informaticos]

Machine still works with battery connected?
Maybe your CD3217 chips are not good, or not properly soldered.

 

[sourcensolutionsonline@gm]

Machine still works with battery connected , the CD3217 I can double check them , when i connect amp meter it would stay and disconnect by itself and reconnect again and if I check under my thermal camera U6903 keeps getting warm , I have purposely replaced it 2 times , as soon as i put a new U6903 PP3V3_G3H_RTC has proper diode mode reading to ground, 0.339 but as soon as I connect the USB AMP METER then when i go back to take the diode mode reading PP3V3_G3H_RTC drops to 0.070 but still creating 3.3v I will resolder the CD3217 chips , U2800 was also replaced would that have anything to do since the USB AMP meter when connected to the Macbook not staying stable on 5v , in the short video that i uploaded , You could ve seen that the amp meter keeps switching off by itself every 10 -15 seconds.

 

[2informaticos]

"as soon as I connect the USB AMP METER then when i go back to take the diode mode reading PP3V3_G3H_RTC drops to 0.070"
Allow 10-15s since power is removed, before checking diode mode, or ohm scale on any power rail.

Was U2800 damaged any way, to replace it?

 

[sourcensolutionsonline@gm]

Yes,

U2800 Power line PP3V3_TBT_X_SX was shorted that was why reballed another U2800 and replaced and that short was gone.

 

[2informaticos]

Did you replace it from donor board, same model?
Did you test MLB without it soldered (on charger)?

 

[sourcensolutionsonline@gm]

I removed both of CD3217 chips and replaced them I realised they were both well soldered , but my issue is not there , is there anywhere else that is causing my issue? Please advice.

 

[sourcensolutionsonline@gm]

Today at 7:25 PM

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• #133

Did you replace it from donor board, same model?
Did you test MLB without it soldered (on charger)?


I got the U2800 From a A1989 which was the same markings on the chip with the A2289 , I did not understand whats the MLB. Can you clarify it for me please?

 

[2informaticos]

Main Logic Board...

So, did you test the machine before soldering U2800?

Post U7000 basic voltages; P_IN, AUX_DET, VDDIO1P8, SMC_RST_IN, VDDA/P, AUX_OK, A/BMON.
Check R/C7030/40 and their traces.
You may need to change Q7030/40.

 

[sourcensolutionsonline@gm]

Ok I will do that.

 

[sourcensolutionsonline@gm]

I did not get to reply to the first question, After I removed U2800 i Did not make any test , I went straight ahead and reball the harvested U2800 and replace it , I will proceed to conduct the following suggestions and will let you know .

 

[sourcensolutionsonline@gm]

Here are the Voltages of the following lines ,

1- P_IN = 10.41V
2- AUX_DET = 1.26V
3-VDDIO1P8 = 1.8V
4- SMC_RST_IN = 0.0V
5-VDDA= 5.14V
6-VDDP = 5.13V
7-AUX_OK = NC PAD
8- A/BMON=0.0V

R7030/40 = 0.2 OHMS
C7030/40 is solid and intact = 0.474 diode mode reading

Q7030/40 looking fines in shape and diode mode reading is normal but i am not too sure if they are doing their Jobs, I havent replaced them yet , would i be able to find them from a donor A1989 I meant Q7030/40 Wouldnt U7000 Cause the issue too? Please advice if i should replace Q7030/40
Thank ou very much .

 

[2informaticos]

I've expected to get these readings on charger alone, without battery connected.

"2- AUX_DET = 1.26V"
Be sure R7020 is not damaged.
Else, AUX_DET should be 2.5V aprox, with 10V at R7020.