[Rick24wag]

Hello, last week my daughters borrowed my 2016 m235i convertible and they called me saying it won't start. When I got there i saw a couple errors about the drivetrain and another error about the fuel pump. The car has 40,000 miles and I've never had a problem with it. The display would come on and lights would work but it wouldn't start. I had it towed home.

I tried to charge the battery with a battery charger but I got an error saying there was an error with the battery (I can't remember exactly the error but I never saw it before and it would happen within 10 minutes. The charger was a normal battery charger that I connected under the hood).

I downloaded ProTools and connected it and found some errors but then I did a system restart (i can't remember exactly what it was called) and after that the car is totally dead. I was pretty sure the battery was low and maybe that was the issue. When i put a multimeter on the battery i only get around 4.5 volts.

I then bought a CTEK MXS 5.0 trickle charger and that was going but it started to rain yesterday and my wife on her own unplugged it in stage 2. It ran for about 4 hours and the volts on the battery stayed exactly the same at 4.5 volts.

I bought a new battery but I can't get into the trunk. Even if i jump the car for 20 minutes nothing happens. No power, lights, console, nothing! I wanted to check with you guys before I took it in. I never used ProTools before.

I had been in the car a lot with it turned off since the problem started so I'm sure the battery was very low plus its as old as the car as well so I'm sure it needs to be replaced. Also can i put it into neutral in the compartment under the gear shifter or do i need to go under the car? Thanks so much for the help.

[123Britt]

Need a new battery & register it as well as Code vehicle if amp rate is different -- without this you may find yourself replacing the battery sooner than later.

[TrboMike]

20 somethings will sit in a car for hours with engine off, headlights on, fan on, stereo on. "Why would the battery die it started yesterday?"

[Rick24wag]

Originally Posted by 123Britt

Need a new battery & register it as well as Code vehicle if amp rate is different -- without this you may find yourself replacing the battery sooner than later.

I tried to jump it from a car that also had a very low battery so when i put a new battery in the jumper car I was able to jump the bmw . I put a new battery in the bmw but it still wouldn't start. I took it in an the ECU was broken so they ordered a new and and they have been updating the ecu for 2 weeks now. I'm not sure what they are doing but it shouldn't' take this long.