Steering ignition switch lock

Does the vehicle start an run ?Can you turn the key to the off position ? And the key won't come out ? Did you try some key graphite ( lube ) ? New lock cylinder need maybe . Or is it a problem with
Steering Column Electric Park Lock
If the vehicle is equipped with a floor-mounted console gear shifter, an added safety feature is an steering column electric park lock system in the steering column. The steering column electric park lock system prevents the steering wheel from being locked when the transmission is in gear and the vehicle may be moving. The column ignition lock system consists of a steering column electric park lock and a park position switch, that is located in the A/T shift lock control switch. The steering column electric park lock contains a spring-loaded pin that mechanically prevents the ignition key cylinder from being turned to the Lock position when the transmission is not in the Park position. If vehicle power is lost or the transmission is not in the Park position, the operator will not be able to turn the ignition key to the Lock position and will not be able to remove the ignition key from the column.

What year is it ? Does yours have floor mounted gear shifter on the console ?
Ignition Lock Cylinder Control Actuator
If the vehicle is equipped with a floor mounted console gear shifter, it has a ignition lock cylinder control actuator system in the steering column. The ignition lock cylinder control actuator's purpose is to prevent the ignition key from being turned to the OFF position when the transmission is in gear and the vehicle may still be moving. The column ignition lock system consists of a ignition lock cylinder control actuator , and a Park position switch that is located in the automatic transmission (A/T) shift lock control switch. The ignition lock cylinder control actuator contains a pin that is spring loaded out to mechanically prevent the ignition key cylinder from being turned to the Lock position when vehicle transmission is not in the Park position. If vehicle power is lost, and/or the transmission is not in the Park position the operator will not be able to turn the ignition key to the Lock position and will not be able to remove the ignition key from the column.

What make vehicle ? Most all vehicles have a safety system .Don't try an force anything you'll break it !
Electronic Park Lock (EPL)/Ignition Lock Cylinder Control Actuator: If the vehicle is equipped with automatic transmission and a floor mounted console gear shift, it has an ignition lock cylinder control actuator system in the steering column. The ignition lock cylinder control actuator purpose is to prevent the ignition key from being turned to the OFF position when the transmission is in any position other than PARK and the vehicle may still be moving. The column ignition lock system consists of an ignition lock cylinder control actuator, and a park position switch that is located in the automatic transmission shift lock control switch. The ignition lock cylinder control actuator contains a pin that is spring loaded to mechanically prevent the ignition key cylinder from being turned to the lock position when the vehicle transmission is not in the PARK position. If vehicle power is lost, and/or the transmission is not in the PARK position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column. They also have this on column mounted shifters !

Most if not all vehicles have a Electronic Park Lock (EPL)/Ignition Lock Cylinder Control Actuator: If the vehicle is equipped with automatic transmission and a floor mounted console gear shift, it has an ignition lock cylinder control actuator system in the steering column. The ignition lock cylinder control actuator purpose is to prevent the ignition key from being turned to the OFF position when the transmission is in any position other than PARK and the vehicle may still be moving. The column ignition lock system consists of an ignition lock cylinder control actuator, and a park position switch that is located in the automatic transmission shift lock control switch. The ignition lock cylinder control actuator contains a pin that is spring loaded to mechanically prevent the ignition key cylinder from being turned to the lock position when the vehicle transmission is not in the PARK position. If vehicle power is lost, and/or the transmission is not in the PARK position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column. Or it has
Linear Shift Assembly: If the vehicle is equipped with a column mounted gear shift, it has a linear shift assembly on the steering column. The linear shift assembly has a cable that runs from the linear shift assembly to the ignition lock cylinder case. The purpose of this cable is to prevent the ignition key from being turned to the OFF position when the transmission is in gear and the vehicle may still be moving. The linear shift assembly cable contains a pin that is spring loaded to mechanically prevent the ignition key cylinder from being turned to the lock position when the vehicle transmission is not in the PARK position. If vehicle power is lost, and/or the transmission is not in the PARK position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column.
Your best bet is to take it to a ASE certified repair shop or the dealer ! The fix involves taking the steering column apart an or the floor shifter assembly ! Also electrical test to determine what is the problem !
Your

Ignition Lock Cylinder Control Actuator
If the vehicle is equipped with a floor mounted console gear shifter, it has a ignition lock cylinder control actuator system in the steering column as an added safety feature. The ignition lock cylinder control actuators purpose is to prevent the steering wheel from being locked when the transmission is in gear and the vehicle may still be moving. The column ignition lock system consists of a ignition lock cylinder control acutator, and a park position switch that is located in the A/T shift lock control switch. The ignition lock cylinder control acutator contains a pin that is spring loaded out to mechanically prevent the ignition key cylinder from being turned to the lock position when vehicle transmission is not in the Park position. If vehicle power is lost, and/or the transmission is not in the Park position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column. GM has had some problems with this , If you have the console shifter there is a micro switch that when put into park a linkage pushes on this micro switch closing the circuit to ignition lock cylinder control actuator allowing you to remove your key ! These linkages fall out causing this problem ,an have electrical wiring problems as well ! I fixed a 2006 Chevy cobalt that had this same problem by getting a used shifter assembly at the auto salvage year ! cost $20.00 . There mite be a access hole under the bottom of the steering column with a release button up inside !

Fixing stuck key in your gmc envoy same as a blazer !
Ignition Lock Cylinder Control Actuator
If the vehicle is equipped with a floor mounted console gear shifter, it has a ignition lock cylinder control actuator system in the steering column as an added safety feature. The ignition lock cylinder control actuators purpose is to prevent the steering wheel from being locked when the transmission is in gear and the vehicle may still be moving. The column ignition lock system consists of a ignition lock cylinder control acutator, and a park position switch that is located in the A/T shift lock control switch. The ignition lock cylinder control acutator contains a pin that is spring loaded out to mechanically prevent the ignition key cylinder from being turned to the lock position when vehicle transmission is not in the Park position. If vehicle power is lost, and/or the transmission is not in the Park position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column.

SECTION 211-05: Steering Column Switches 1998 Expedition/Navigator Workshop Manual REMOVAL AND INSTALLATION Procedure revision date: 02/11/2000 Multifunction Switch Removal

1. Disconnect the battery ground cable (14301).

1. Remove the ignition switch lock cylinder (11582).
   1. Insert the ignition key into the ignition switch lock cylinder and turn to the RUN position.
   1. Insert a punch through the hole in the lower steering column shroud and push the ignition switch lock cylinder release tab while pulling out the ignition switch lock cylinder.

1. Twist the tilt wheel handle and shank (3F609) and remove.

1. NOTE: Move gear selector to lowest position to access steering column opening cover.
   Release the four clips and remove the steering column opening cover.

1. Remove the upper and lower steering column shrouds.
   1. Remove the three screws.
   1. Remove the lower steering column shroud.
   1. Remove the upper steering column shroud.

1. Remove the multi function switch.
   1. Remove the two screws.
   1. Disconnect the electrical connectors.
   1. Remove the multi function switch.

Installation

1. NOTE: When the battery (10655) is disconnected and reconnected, some abnormal drive symptoms may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 mi) or more to relearn the strategy.
   To install, reverse the removal procedure.

Check the ignition switch on top of the steering column,to see if it is locking up before it goes into start position.You will have to lower the column down to access the ignition switch,it has a rod going to it from the key cylinder,if it is not locking up,then replace the key cylinder.You will have to remove the ignition switch to check it,two screws.

Ignition Lock Cylinder Control Actuator
If the vehicle is equipped with a floor mounted console gear shifter, it has a ignition lock cylinder control actuator system in the steering column as an added safety feature. The ignition lock cylinder control actuators purpose is to prevent the steering wheel from being locked when the transmission is in gear and the vehicle may still be moving. The column ignition lock system consists of a ignition lock cylinder control acutator, and a park position switch that is located in the A/T shift lock control switch. The ignition lock cylinder control acutator contains a pin that is spring loaded out to mechanically prevent the ignition key cylinder from being turned to the lock position when vehicle transmission is not in the Park position. If vehicle power is lost, and/or the transmission is not in the Park position the operator will not be able to turn the ignition key to the lock position and will not be able to remove the ignition key from the column.

Lock Cylinder Functional
Removal

1. NOTE: The following procedure applies to vehicles that have functional ignition switch lock cylinders (11582), lock cylinder keys are available for these vehicles or the lock cylinder key numbers are known and the proper key can be made.
   
   Disconnect battery ground cable (14301). Refer to Section 14-01 .
   

1. Turn ignition switch lock cylinder to RUN position.
   

1. Place a 3.17 mm (1/8-inch) diameter wire pin or small drift punch in hole in lower steering column shroud (3530) under ignition switch (11572). Press retaining pin while pulling out on ignition switch lock cylinder to remove it from steering column lock cylinder housing (3511).
   

Installation

1. Install ignition switch lock cylinder by turning it to RUN position. Insert ignition switch lock cylinder into steering column lock cylinder housing. Make sure ignition switch lock cylinder is fully seated and aligned in interlocking washer before turning ignition switch lock cylinder to OFF position. This will permit cylinder retaining pin to extend into steering column tube flange hole.
   

1. Rotate ignition switch lock cylinder, using lock cylinder key, to ensure correct mechanical operation in all positions.
   

1. Connect battery ground cable.