Chevrolet HHR 2010 Owner's Manual page 132

Column Lock Release
For vehicles with an automatic transmission, the
following procedure allows the ignition to be turned to
LOCK/OFF and ignition key to be removed in case of a
dead battery or low voltage battery.
1. Make sure the shift lever is in P (Park).
2. Remove the cover from the bottom of the steering
column.
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3. Locate the plunger.
4. Press and hold the plunger while turning the ignition
key to LOCK/OFF. Remove the key.
Have the vehicle serviced at your dealer/retailer as soon
as possible.