HONDA FCX - Manual (Page 16)

Second-Best Method for Preventing
Current Flow and Hydrogen Leakage
Disconnect the 12-volt battery negative cable
and the negative DC-to-DC converter cable,
then turn off the manual hydrogen shut-off
valve.
This method should be used only if the key
switch is in the ON (II) position, and you cannot
reach the key but you can reach under the hood.
Disconnecting the 12-volt battery negative cable
and the negative DC-to-DC converter cable turns
off the fuel cell system and all the motors,
preventing high voltage from flowing into the
cables. It also cuts power to the airbags and the
seat belt tensioners within 3 minutes, and
prevents the propulsion motor from being
restarted.
Turning off the manual hydrogen shut-off valve
stops the hydrogen flow from the fuel tanks.
To use this method, do this:
1. Open the hood, and locate the 12-volt battery
on the passenger’s side.
2. Using a 10 mm wrench or pliers, disconnect
the 12-volt battery negative ground bolt.
3. Using the wrench or pliers, disconnect the
negative DC-to-DC converter cable ground
bolt.
Emergency Procedures
Continued
12
12V
Battery
12V Battery
Negative
Ground Bolt
Negative
DC-to-DC
Converter
Cable
Ground Bolt