Chevrolet 2007 TrailBlazer Owner's Manua page 433

Notice: Ignoring these steps could result in
costly damage to your vehicle that would
not be covered by your warranty.
Trying to start your vehicle by pushing or
pulling it will not work, and it could damage
your vehicle.
1. Check the other vehicle. It must have a
12-volt battery with a negative ground system.
Notice: If the other vehicle's system is not a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
vehicles with 12-volt systems with negative
grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper
cables can reach, but be sure the vehicles are
not touching each other. If they are, it could
cause a ground connection you do not
want. You would not be able to start your
vehicle, and the bad grounding could damage
the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake firmly on both vehicles
involved in the jump start procedure. Put an
automatic transmission in PARK (P) or a
manual transmission in NEUTRAL before
setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer
case is not in NEUTRAL.
Notice: If you leave your radio or other
accessories on during the jump starting
procedure, they could be damaged. The repairs
would not be covered by your warranty.
Always turn off your radio and other
accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles.
Unplug unnecessary accessories plugged into
the cigarette lighter or the accessory power
outlets, if equipped. Turn off the radio and all
lamps that are not needed. This will avoid
sparks and help to save both batteries. And it
could save the radio!
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