GMC Hybrid 2006 Owner's Manual page 49

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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