GMC Hybrid 2007 Owner's Manual page 55

To access the battery disconnect switch and
disconnect battery power, do the following:
1. Turn the ignition key to LOCK.
2. Grab the tab at the top of the access door
and pull the top of the door out.
3. Pull the access cover up and out from the
access opening.
4. Locate the battery disconnect switch.
5. Turn the switch counterclockwise until it stops.
The 42-volt battery power is now disconnected
from the vehicle.
This switch can be removed when it is in the
off (no power) position.
When you are ready to reconnect battery
power to the vehicle, turn the switch clockwise
until it stops.
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