Computers Can Be Such a Drag--on Farm Equipment
Dec 12, 2012
Many of the computers and electronic gadgets in modern farm equipment draw a little power even when the key switch is off. As long as they're connected to a battery they draw a few milli-amps of current to power built-in memories, clocks and other functions. A few milli-amps for one computer, a few milli-amps for a GPS system, a few milli-amps to feed a memory in a monitor display, and before long you've got enough of a "draw" to drain a machine's battery if it's stored for more than a few weeks.
The owner's manual for a brand new combine recommends that owners switch off the machine's built in battery disconnect switch if the combine will be left idle for more than two weeks. Interestingly enough, the manual recommends completely disconnecting the negative leads on battery if the machine will be stored for more than 90 days.
(If I get a chance to talk to an engineer, I'm going to ask what difference it makes if the battery disconnect switch is turned off, compared to disconnecting the ground cable.)
Check your owner's manual(s) before disconnecting all electrical power. On cars and pickup trucks, disconnecting batteries can wipe the memories of radio station presets and other convenience functions. Farm equipment may have similar losses of reprogrammable information, but totally removing battery power shouldn't harm any electrical components and will improve battery longevity.
Be sure to fully charge batteries before disconnecting them, and occasionally trickle charge them if storage lasts longer than 3 months.