Last Thursday after our car had been stood for over a week, it started as normal. We took our caravan away, and navigated to our destination using the car's sat-nav system (Mk 4 DVD). On Friday morning, I unlocked the car and all was apparently normal. Later in the morning, as we were going out for a walk I locked it again. Once again, nothing unusual. However, several hours later, when I attempted to unlock the car using both remotes, it was dead. I opened the door using the key and tried the ignition, whereupon there was a faint glow from the lights - battery flat. I cherged the battery on the caravan's charger overnight and re-fitted it to the car. Since then there have been no problems again. The only thing that I can think is that I did not have the exact location listed on the sat-nav so navigated to the nearest village. Having passed that, the unit kept telling us to "turn around when possible", and I didn't cancel the destination when we arrived. Therefore is it likely that each time I unlocked the car the sat-nav was still trying to guide us, and would it flatten the battery? As said above, the battery now seems totally fine again. Any ideas would be appreciated? Thanks.