Global Machinery Company Sierra 1999 - Manual (Page 87)

yellow blue
2-15
NOTICE:
If your key seems stuck in LOCK and you can’t
turn it, be sure you are using the correct key; if
so, is it all the way in? If it is, then turn the
steering wheel left and right while you turn the
key hard. But turn the key only with your hand.
Using a tool to force it could break the key or the
ignition switch. If none of this works, then your
vehicle needs service.
Key Release Button (Manual Transmission)
The ignition key cannot be
removed from the ignition
of manual transmission
vehicles unless the key
release button is used.
To remove the key on manual transmission vehicles,
turn the key to OFF, then press the button and turn the
key to LOCK. Do not hold the button in while turning
the key to OFF. Pull the key straight out.