MacBook not recognizing battery, not even in coconutbattery

"Try resetting the SMC

Connect the power adapter to the Mac. On the MacBook / Pro's keyboard, hold down the Shift+Control+Option keys and the Power button at the same time. Release all keys and the power button at the same time – the little light on the MagSafe adapter may change colors briefly to indicate the SMC has reset.

That failing zap the PRAM

Shut down your machine. Yes, all the way down, not sleep or logging out.

Press the power button and then press command-option-p-r. ...

Hold those keys down until your Mac reboots again and you here the startup chime.

Let go of the keys and let your Mac reboot normally."

"1. If the Macbook turns off straight away when the charger is unplugged, will most likely be the battery.

2. If you unplug the charger and the screen goes off (but the sleep light or fan still spins for a bit before turning off, showing it is running from the battery) it will be either the SDA or SCL resistors, which allow the battery to communicate with the SMC.

Would recommend getting a battery if it is the first situation. If it is the 2nd, try a new battery anyway before looking into the logic board. Visually check the board for liquid damage or burnt components too, especially around the 28 pin IC to the right of the RAM and above the battery connector.

EDIT: SDA and SCL resistor location"

"I would recommend you start by double checking the battery to logic board connection. Did you damage one of the wires from the battery?

Otherwise, I agree you'll need a second battery here to double check things."

"I have the same problem. Please help me

I plugged my computer for charging overnight. This morning when I plugged out the wire the displays shut downs quickly and it is not charging. There is no battery information also available in the system information page. Please help me what could be the problem."

"Just had the same issue with someone’s 2012 13” rMBP. However, it just started doing it by itself. Was never disassembled. Charger glowed orange, and I was able to power on if I held down the power button while plugging in the charger, although it ran with fans on full speed, and battery wasn’t recognized.

Checked out the battery and connectors physically, but it looked good, apart from some dust. No swelling or the like. Pressing the power button alone would spin the fans in slow bursts, but nothing else.

Tried SMC and PRAM resets multiple times, didn’t work. Then I tried plugging in the 85w charger from my own 2013 15”, and it turned on instantly, battery recognized too. It was on zero percent charge though, but started charging normally after a few minutes. Maybe the battery was so drained that the smaller charger couldn’t kick it into life - it does have lithium batteries, and this can also happen on 18v power tools lithium batteries, where you have to do a few things before they will charge, if they are completely drained. Normally a Mac will shut down by itself before they drain completely, but I’m not sure what happened in this case. Works now though, also with the smaller charger."

What value of resistance are we looking at on these two resistors.