Ignition Key Lock: Disassembly

Remove the immobilizer antenna assembly.
1. Disconnect the connector.
2. Release two claws using a flat tip screwdriver or similar tool wrapped with a protection tape, and remove the immobilizer antenna assembly.
CAUTION: Do not apply excessive force to disengage the lock of immobilizer antenna assembly. Otherwise they may be broken because those parts are the products made of a plastic.

Fig 1: Disengaging Lock Of Immobilizer Antenna Assembly
Courtesy of SUBARU OF AMERICA, INC.
Release the claws, and pull the key warning switch downwards to remove.

Fig 2: Pulling Key Warning Switch Downwards
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Remove the key lock solenoid.
1. Disconnect the connector.
2. Remove the screws and remove the key lock solenoid.
Fig 3: Removing Key Lock Solenoid
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Replace the key cylinder.
1. Insert the key into the key cylinder, and turn the key to the ACC position.
2. Insert a flat tip screwdriver from the steering lock frame hole (A), and pull the key cylinder until the key cylinder claws touch the steering lock frame stopper (B).
  
  Fig 4: Inserting Flat Tip Screwdriver From Steering Lock Frame Hole
  Courtesy of SUBARU OF AMERICA, INC.
3. Insert a flat tip screwdriver from the steering lock frame hole (A), and release the claws to pull out the key cylinder.
Fig 5: Locating Key Cylinder Claws
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Release the claws and remove the ignition switch assembly.

Fig 6: Removing Ignition Switch Assembly

Courtesy of SUBARU OF AMERICA, INC.