I'm sorry the Tech you requested was unavailable to assist you today. It appears that Tech is currently "Offline". Now that his 15 minute "request lock" has expired, hopefully I can be of some assistance in his place...
When the shifter will not release from Park, first, check the brake lights and see if they are working when you step on the brake pedal.
If the brake lights are NOT working, first, check the fuse #32 in the fuse panel located on the right-hand side of the center console. If the fuse is good or the fuse blows after replacement, then the problem will lie in the Brake Pedal Position Sensor. It's located at the top of the brake pedal arm, under the driver's side dash. This sensor controls the brake lights and also sends a signal to the Shift Interlock telling it to release when the brake pedal is depressed. Carefully inspect the electrical connector and wire harness for any loose, broken, damaged, or rubbed through wires. If the visual inspection checks ok, replacing the sensor will solve the problems.
If the brake lights ARE working, then the problem will lie in the Shift Interlock System. There are a few items here that will need to be tested and inspected, including the shifter assembly itself looking for any broken or damaged parts.
In the meantime however, there is an "over-ride" to release the shifter (unless the problem is a broken rod or spring in the shifter assembly). To override the brake shift interlock, remove the tethered cap on the gear shift bezel with a small screwdriver. With the brake pedal depressed, insert a small screwdriver into the access hole, press down and pull the gear shift lever out of PARK.
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