820-01958 battery not charging, fans run at max


Hi there,

got a MBA A2179 (820-01958) with unknown history but looking clean so far. The Macbook turns on but fan speen increases up to max and it is incredibly slow. Additionally the battery is not correctly recognized (Warning symbol on battery symbol) or charging or running from battery only.
Already tried a known good battery and repairing in DFU mode.
Unforunately I dont know much about the behavior of the Typ-C MacBook Air models and owuld be happy for some help.



Staff member
Unrecognized battery can cause this.
Did you try known good battery, or "new chinese" one?

Check voltage and diode mode on SCL/SDA lines of battery bus; in front and behind Q6950.

Be sure SYS_DETECT_L is correctly pulled down.
Did you connect battery data flex and correctly tighten the big screw?


Yes, you were right again 🙂 My OEM testing battery did get faulty.

Now I have another issue with the keyboard backlight. It's always on and not dimmable. Even if MBA is off. Only turns off if I close the lid.