I don't drive my E1 much. Perhaps once every fortnight. Often the battery is dead and needs to be put on a charger.
However, given the recent holidays, I've driven it a couple of days in the week. It seems my battery (perhaps a year old) drains to the point where it clicks (doesn't crank) within 3-4 days.
My guess is that there's something draining it that fast. Any ideas? It has an alarm, but I checked with the installer and he thinks the battery would only drain over about 2 weeks, not 3-4 days.
I've noticed the door light stays on (but gets brighter when the door opens). Could that be a factor?