Why does the battery in my car go flat after a week if I don't drive it?

The battery in my Peugeot 308CC was draining frequently, especially in cold weather. I replaced the battery seven months ago but it still goes flat after a week if the car isn't used. Peugeot dealer says to drive it more often. Cannot help but think there's an underlying problem with this cars electrical system. Can you offer any advice?

Asked on 24 October 2017 by Roy McNee

Answered by Honest John
Yes, there will be and because the battery has already been drained so often it will have lost its capacity to hold a full charge so will only get worse. Call in a local car electrical specialist. Possibly something to do with the roof mechanism. A fault with the interior light switch would drain the battery overnight.
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Much improved over 307CC. Reasonable range of engines and transmissions.

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