Hello. Sorry for the long post, but I am trying to decide if this is a simple battery replacement, or potentially something more complicated.

I bought an open box MacBook Air M1 2020 A2337. Seller claimed it was never used. Visually, it appears pristine.

On arrival, the battery was completely flat. Computer powers up and boots fine. Battery status showing 1% and charging, 1 cycle. coconutBattery showing 0 mAh and ~6 watts.
After some hours, the battery status did not improve. Restore via DFU did not help.

I connected the power adapter to a Kill-a-Watt...

My question pertains to understanding the control circuity inside a Dell PT434 type battery used in Dell E6400, E6410 and other Dell notebooks?

Does anyone have a circuit diagram for the inside of a Dell PT434 battery and/or a description of how the control lines work to control this battery?

My reason for asking is I have a battery which I cannot get to charge beyond 1% in a Dell E6410 or E6400.
The LED bar graph charge indicator on the battery shows one LED lighted when the info button is pressed.
I have tried multiple different Dell power adapters. My Dell...

Hi guys,

If I unplugged the battery and the charger, then plug the battery then the charger, it charges without problem.
Then if I unplug the charger and plug it back, it won't charge anymore.
In the first case, main voltage is regulated at ~12.5V and charges the battery.
After unplugging the charger, main voltage drops to battery voltage at ~11.5V.
After replugging the charger, main voltage stays at ~11.5V and won't go up to ~12.5V again.

I found C520A (2.2µ after current sensor from USB-C source) completely burnt and removed it properly. I cleaned...

Hi Gang, Im working on Macbook Pro A1990, the battery connector was torn off during friend trying to replace battery. I soldered on the connector back, and created traces. The battery does charge (according to amp meter), and does power on battery only. But the signal detect line maybe done incorrectly, and the macbook shows "X" over battery icon, and "Service Recommended" on new battery

Can somebody point me to which of these connector pins is responsible for battery detect/data line? Pin 4 on schematic had a nub on the trace, im not sure if that is important,...

I am hoping to get some advice. I have a 2020 13" Macbook Pro - A2251 that wouldn't turn on. I have done lots of electronics repair in the past but never on Macbooks. I have had this laptop sitting around and I finally decided to take a look at it and see if I could spring some life into it.

First, it wouldn't boot up at all. I did a DFU restore and managed to get it to power on. Did a full restore but the battery was dead and wouldn't charge. I put in a new battery in it but now it won't boot up when the new battery is connected. I ordered a second new battery just in case,...