MacBook Pro A2141 replaced battery not booting from battery not charging. Works with power suppy

[Schluchti45]

Hello,

i ask if someone has a hint for me. I have a A2141. The original battery died and i replaced it with a new one form Ifixit. After the replacement the MacBook Boots only with the power supply.
Coconut Battery is recognize the battery but it is not charging. When i remove the power supply the MacBook is immediately dead.

[mon2]

If available as an option, consider to source yet another known good battery from Amazon or similar. This is only to rule out the battery as a defect (which is quite possible). You can always return the battery back to Amazon if it is not required. Aside from this, you will need proper tools like a multimeter + screwdriver set to open up the unit for inspection. Hot air soldering tools or someone with these if parts need to be replaced.

Ifixit is apparently a stable outfit for parts so you can ask them if they have come across DOA batteries. Assuming not, we need to dig deeper to take some measurements.

Can you post a good pic of what the Coconut Battery tool reveals?

[piernov]

Heard from other technicians that iFixit batteries are no better than other random suppliers. They may provide a little bit better customer service than the cheapest Aliexpress listing though…

[Stephen]

Do the fans spin when you turn on the computer while the battery is connected? If so this would rule out that the battery is defective even if it is new. Very common to get bad batteries from suppliers. It is always better to remove a pre-owned battery and reseal it from an A2141 if you have that chance. They seem to be more reliable than new ones lately.

[Schluchti45]

the fans turn when the battery is connected but only with the power supply but it is not charged.

[oxonater]

Hi

Sounds silly but do you have the correct BMU flex had a few issues myself in the past with these (even new ones supplied by Apple)
Make sure there is a good connection failing this I/O boards could also be and issue have you tried all 4 ports with same result ?

[mon2]

This logic board was able to charge the battery ok before this replacement?

The BMS (battery management) flex cable is separate from the rather beefier cabling used to power the unit. Is the larger & beefier cable firmly attached to the main board? The logic board will be able to detect the serial #, brand of the battery using the smaller BMS / BMU flex cable but will show 0 charge current if the other cable is not properly mating with the logic board.

Be sure the wide head screw has been applied to pressure fit the battery pcb contacts onto the main logic board. If that is missing or is a loose fit, the charge current will be 0A as showing in your posted screens.