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 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,...

Hi everyone.
Quick backgrounhd story: Macbook came to me stuck on 5V. According to repair.wiki I could have an issue on L7800. Indeed it was not passing signal through. And I did have an issue on PP5V_BSTLQ_VOUT_SPMU line. I found a cracked cap (C7800) and replaced both failing components.
Now it negotiates 20V and the computer starts, but I receive the message "you are now running on reserve battery power", as shown on the attached picture. It happens with or without a battery connected. So I am discarding a battery issue, for now (it may be bad, but I will only know for...

Hi everyone,
I have a MacBook Air A2179 in my hands that had power problems (5V to the USB-C port intermittently).
After a first inspection I could see that the D3302 protection IC was burnt out, so I replaced it but the problem was not solved, it seems like intermittent 5v input.
I then replaced the two u3200s (CD3217B12ACE) and now I have stable 20 volts and the macbook has turned back on.
Unfortunately I have a further problem, it works very slowly and the fan runs at maximum and if I disconnect the charger it turns off, it's as if the battery was disconnected.
...

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,...