When my MYD4 battery died after 5 years service the tech from RACQ told me that I should always lock it when it sits idle (in the garage for weeks on end) as the electrics wake up regularly to check the vehicle status thereby running the battery down. This may not make a notable effect on a new battery but will be more draining as the battery gets older and if the vehicle sits idle for longer periods.
Cheers
Jaybee

