Bimmerfest - BMW Forums - View Single Post - Increased Battery Discharge issue
View Single Post
Old 12-05-2011, 06:44 AM
terri_atl terri_atl is offline
Officially Welcomed to the 'Fest
Location: Atlanta
Join Date: Nov 2011
Posts: 343
Mein Auto: 2011 328i Convertible
Originally Posted by yikes98 View Post
It is what it is. If more goes out (closed-circuit current consumption of 10 - 40 mA) than in you are going to run out of juice. The alternative design might be to not have sleep mode for all the computers and have it shut down like Windows, then you can wait 10 minutes before your car can boot and drive off, that's if you don't get the blue screen of death.

From BMW service.

Long immobilization period
The vehicle was parked for a very long period. The vehicle has a standard closed-circuit current consumption of 10 - 40 mA, depending on the equipment fitted. This leads to slow but continuous battery discharge. Depending on the state of charge of the battery when the vehicle is parked, the residual capacity necessary to start the vehicle is reached after an immobilization period of approx. 4 - 12 weeks. If possible, point out these facts to the customer.

This is not me, my car is a daily driver .

Unfavorable driving profile
The battery can be depleted due to unfavorable driving characteristics of the customer:
- In the case of extreme short-distance driving, it is possible that starting the engine takes more energy from the battery than is charged in the subsequent trip. The charge balance deteriorates if a great many current consumers are switched on during the subsequent trip.
- Very few trips: If the vehicle is moved very infrequently and the individual trips are not sufficiently long, it is possible that during the immobilization period more energy is taken from the battery by normal closed-circuit current than is charged while the vehicle is being driven.
If possible, point out these facts to the customer.
I guess that would be me?? But how extreme short-distance are we talking about. All of a sudden, I am very aware of the number of miles the car went. This morning I checked it was a 7 miles one way. So are we saying if the car is parked, the energy taken from the battery is more than the amount of energy charged during driving? What is normal closed circuit current? The BMW tech told me it takes one hour for the car to completely shut down. So electricity is used during this one hour?

2011 328i Convertible | Black Sapphire Metallic | Black Dakota Leather | Bamboo Anthracite Wood Trim| Sports | Premium | Comfort Access | Heated Seats | Navigation | Harmon Kardon | iPod/USB
Reply With Quote