2005 BMW 745i Starting issues

[AhmerShah1]

So my wife's BMW is only driven very little and, therefore, its battery has a tendency to run out of charge. I have bought a trickle charger to address that. So the last time the battery died, I first jump started it, let it idle for 15 minutes, and then turned it off, and plugged the trickle charger. Well couple of hours later, the car alarm went off, so I unplugged the trickle charger. Following day, I tried to start the car, and it would not start. So I tried to jump start it from another car first, to let it idle for 15 minutes, to connect the trickle charger to start the proper trickle charging process. Well this time, the car just would not crank up...It tries to start, the engine turns, but engine is acting like its suffocating (vacuum leak or something) and then it dies. Trickle charger is not doing anything either. Regardless of what I do, the car just does not want to start. Please advise.

[jclausen]

First of the battery is probably done they don't like draining down and not getting fully charged up, plus all the sevens were up graded to an agm when the battery was changed, plus the battery needs to be registered when replaced. Also there is an airport switch for when the car sits a lot open the trunk on the passenger side is the fuse box electrical panel get a flash light stick your head in there shine the light up at the top of the panel there is slider switch when is on a number of electrical items won't take battery voltage. If you start the car and the switch is in the wrong position a message will come on in the I drive. Also don't listen to the radio or talk on the phone with out the car running, the battery's have very little reserve capacity, you will probably get a battery discharge message in about 15 mins if you did and finally connect the battery tender to the jumping points in the engine compartment, run the wires out shut the the hood and lock the car, just leave it on until you need the car. I like the battery tender made by battery tender I have had one for years and works great. Basically the car probably could have really used 2 battery's when they built it, so the one battery is ok but will not put up with sitting at all if not kept in a fully charged state

[AhmerShah1]

I made a video of the behavior of the car when its connected to another car's battery in an attempt to jump start. And this is what the car is doing https://drive.google.com/file/d/1fXSaZyCUStYW7Vim70QkQmsmUzRl1FPZ/view?usp=sharing . Please advise. Thanks for your help

So my wife's BMW is only driven very little and, therefore, its battery has a tendency to run out of charge. I have bought a trickle charger to address that. So the last time the battery died, I first jump started it, let it idle for 15 minutes, and then turned it off, and plugged the trickle charger. Well couple of hours later, the car alarm went off, so I unplugged the trickle charger. Following day, I tried to start the car, and it would not start. So I tried to jump start it from another car first, to let it idle for 15 minutes, to connect the trickle charger to start the proper trickle charging process. Well this time, the car just would not crank up...It tries to start, the engine turns, but engine is acting like its suffocating (vacuum leak or something) and then it dies. Trickle charger is not doing anything either. Regardless of what I do, the car just does not want to start. Please advise.

[stevebratt]

do you have an error code reader? sounds like somehtign gone.

have you checked fuses around the car?

[AhmerShah1]

Battery has a full charge now but the car is still not starting. I have had it towed to two independent mechanics but they are unable to figure out the issue. Engine is turning but the car is not starting.