BMW 1 Series - No charge

I have a 2008 BMW 118d owned from new with 30,000 miles. In the last few weeks the clock has lost the time three times, the low battery light has come on sometimes on start up, the stop/start has quit and today the failed electronics light came on. I have spoken to the local dealer by telephone and was told that the car is not being used enough and the battery needs charging or replacing.

I'm sure that 30,000 miles in three years is average usage. The mileage is a mix of short and longer runs, although there have been quite a lot of shorter runs recently with the odd 50 mile plus trip. Does the low battery diagnosis seem reasonable to you? The warranty expires soon so if there is an underlying problem I need to get it sorted as soon as possible.

Asked on 21 January 2010 by GT, via email

Answered by Honest John
The diagnosis is exactly right. This Efficient Dynamics engine has a regenerating alternator that only charges on the overrun. If you do too many short runs back to back you will not charge the battery sufficiently. The car is unsuitable for repeated short runs from cold.
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Great to drive and superbly built. Wide choice of models, improved from 2007 with Efficient Dynamics. 118d is super economical.