Modules - Battery Drain

[BimmerBri84]

Hello all,

I was told by the dealership that there is a potential module that is staying on while the car is shut off. This module has drained my battery in which I am having to get a jump almost daily. They ran an energy diagnostic on my car which is how they found it to be the module. They did a system update in hopes this would solve the problem instead of replacing the module. After the update, all looked good until I started the car the next morning... dead again!

Long story short... I am getting the module replaced. The mechanic said there are about 27 different modules and that he will need to rerun the energy diagnostics test to see if its the same module or a new one since doing the update. I was quoted at $1600 for this module... Does that sound about right?

What are these modules? What do they do?

Thank you,
Milani

[jclausen]

There are indeed many modules, when you hook up BMW ista you will see a page full modules. In short the modules work on a network system talking to each other, so if one module is having a problem then it can wake the car up and drain the battery or effect the other modules on the network. And most if not all of these modules are not plug and play meaning they have to be programmed and if the programming is an old version in the car then you usually can not just program the one module, you have to program the complete car. And to find the offending module can take time, luckily for the engergy diagnostics it can show what module woke up.

[BimmerBri84]

Thank you JClausen for the response. Does $450 to $1600 sound about right for the part cost?

[BimmerBri84]

*UPDATE*

Module was replaced, but still did not crank up this morning. He ran the electrical energy diagnostics test to pinpoint the issue before installing the module, but obviously there is something else. He also confirmed it wasn't my alternator... Not sure what to do anymore with my lemon BMW. :-(

[Johnny Kim]

*UPDATE*

Module was replaced, but still did not crank up this morning. He ran the electrical energy diagnostics test to pinpoint the issue before installing the module, but obviously there is something else. He also confirmed it wasn't my alternator... Not sure what to do anymore with my lemon BMW. :-(

Any mods on the car?