"BMW Z4-A/C Having Trouble After Charging The Dead Battery"

BMW Z4 Air Conditioning Vents

I don’t know the exact reason, but I had my battery die yesterday. I jump started it using a portable battery and left it running around 30 minutes just to make sure it’s recharged. But for some reason my BMW Z4 Air Conditioning is not working. It blows air from the vents, but the AC light never turns into green, so its not blowing hot or cold air. I read somewhere it’s kind of a safety feature, but I don’t know how to reverse it back.

Answer: Unusual things can happen when the battery dies and the voltage is brought back up without taking the voltage down to zero, a condition known as a “dirty boot” in the computer world. I recommend disconnecting the battery for a minute or so to reset everything and see if that fixes it.