The battery on my new car keeps going flat - what could be the problem?

I have a 2018 Alfa Romeo Giulia with 8000 miles on the clock. The car was running fine until the end of October, but I parked it in a garage overnight for around 11 hours and the next morning the battery was totally flat. Roadside Assist was called out and confirmed the battery was totally flat, but a quick boost and the car started no bother. The same thing happened a second time so I took it to a dealer the next day but they could not find any faults. The battery was checked and is holding a full charge. Any ideas?

Asked on 18 December 2018 by Brendan Murphy

Answered by Alan Ross
It would appear that you have a parasitic drain (i.e some circuits are live even though the car is switched off). Given the age of the vehicle and the fact it's still under warranty, we would go back to the dealership and get them to carry out a parasitic drain test.
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