Chevrolet 2010 HHR Owner's Manual page 135

The ignition switch has four different positions.
In order to shift out of P (Park), the ignition must be in
ON/RUN or ACC/ACCESSORY and the brake pedal
must be applied.
This position locks the steering column
when the key is removed. The key can only be removed
in LOCK/OFF.
On vehicles with an automatic transmission, the shift
lever must be in P (Park) to turn the ignition switch to
LOCK/OFF.
On vehicles with a manual transmission, the ignition
switch can be turned to LOCK/OFF in any shift lever
position.
The steering can bind with the wheel turned off center.
If this happens, move it from right to left while turning
the key to ACC/ACCESSORY. If this does not work,
then the vehicle needs service.
If you have a manual transmission removing the
key from the ignition switch will lock the steering
column and result in a loss of ability to steer the
vehicle. This could cause a collision. If you need
to turn the engine off while the vehicle is moving,
turn the key to ACC/ACCESSORY.
some of the electrical accessories. It unlocks the
steering wheel and ignition.
This position operates
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