We have been having the parasitic battery drain problem on our 2010 LR2 for several years (battery dead after not driving it for a day or two). We have replaced batteries, done extensive troubleshooting and ultimately had to purchase a charger so we could start our Land Rover when we found the battery was dead on many mornings. Finally our mechanic was able to confirm there is a 500milliamp draw on the battery when the vehicle is off. They were able to reduce the draw to 60milliamps by turning off ALL AUTOMATIC FEATURES before turning off the car (auto climate control, auto headlights, auto windshield wipers, auto Bluetooth connect) and being sure to LOCK THE VEHICLE. By doing these things our LR2 has started reliably for a week now. Apparently the auto features and leaving the car unlocked keeps the computer from going into standby mode which means it's constantly drawing 500milliamps while parked overnight, killing the battery. I'm so curious if this solution works for others. Please let me know!! I am cautiously optimistic that we can rely on our LR2 again.

 

It may be that the real key to your solution is locking the vehicle. I always lock mine because it's parked outside, and I never had this battery drain problem. But I can imagine that if I parked in a private garage that I might leave it unlocked.