Why does the battery in our car keep going flat?
My 2000 VW Beetle has a flat battery. Our mechanic says there's nothing wrong with the alternator or battery. Can you help?
Asked on 3 July 2025 by Betty Grierson
Answered by
Alan Ross
If, as we understand, the mechanic has checked the battery and also the alternator output correctly then we would consider (as should the mechanic) that you have a parasitic drain. This means that after you have switched the engine off and locked the car, there is an electrical circuit still live and as such is draining the battery. It maybe the light in the boot or a interior light or another circuit. Ask your mechanic to carry out a parasitic drain as they should be able to identify where the problem lies.
Tags:
batteries
parasitic drain
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