Macbook A1398 820-00426A

[Instafixx]

Device is dead. If I disconnect the trackpad flex. J8401. Machine turns on. Tried with another trackpad as well. Still the same.

 

[2informaticos]

Check J4801's power lines in diode mode, w/ and w/o trackpad connected.
The connector, or flex may be bad and causes short when inserted.

 

[Instafixx]

Update.
With Tracpad connected I get the apple logo and loading bar till like 25% and then it turns off and loops and does the same thing.
With trackpad disconnected it boots up completely.
Checking with a 85W adapter and no battery

 

[2informaticos]

Tried in safe mode?

 

[Instafixx]

Yes. Still the same.

 

[2informaticos]

Try with known good battery.

 

[Instafixx]

Battery Issue Indeed. Thanks