According to Jack Watkins at VMS, the battery in the DPU is only used for
storing the engine time while the unit is off. Typical life is about 10
yrs and replacement cost is $41.20.
Leon Smith
Dry Creek Airpark
LNCE N63LS
Did
you change the battery in the VM1000 base unit? It has to be changed
about
every 3-5 years. (Mine lasted 7 until it went out--gave funny readings
on
the display)
Doug Johnson