i had my bootlight comming on because i don't slam it shut it was staying on and draining the battery by accident,it never totally flattenend the battery though.
i have noticed the fan sometimes doesn't want to switch off totally,i turn the fan hard to the left and it switches off but sometimes it can creep back on when i'm inside it,could be because it hardly gets used. I always remove my earth lead and leave the car with no battery connected and have no probs,just connect it back up and fire it up.