Honda 1999 Odyssey Owner's Manual page 253

Battery
If you need to connect the battery to
a charger, disconnect both cables to
prevent damage to the vehicle's
electrical system.
The battery gives off explosive
hydrogen gas during normal
operation.
A spark or flame can cause the
battery to explode with enough
force to kill or seriously hurt you.
Wear protective clothing and a
face shield, or have a skilled
mechanic do the battery
maintenance.
Maintenance
On EX model
If your vehicle's battery is
disconnected or goes dead, the audio
system will disable itself. The next
time you turn on the radio you will
see in the frequency
display. Use the Preset buttons to
enter the five-digit code (see page
180).
NOTICE
Charging the battery with the cables
connected can seriously damage your
vehicle's electronic controls. Detach
the battery cables before connecting
the battery to a charger.
On EX model
If your vehicle's battery is
disconnected or goes dead while the
sliding doors are open, the power
sliding door system needs to be
resynchronized (see page 93).