Had the same problem the other day, two weeks away and not enough juice to turn the engine over, you could hear the solenoid engage, but just not enough amps to crank it. I am not sure if it has anything to do with it, but i had left the ipod b&m adaptor plugged in. Not sure if this draws anypower when not connected ... But was the only thong i can think off that might draw power. Going away again tomorrow, so i have invested in a 2.4 watt solar trickle charger. Hopefully that'll solve the issue.