I just replaced the whole ignition switch assy on my 2000 Monte Carlo. The key turned as normal about 5 times and then jammed. The key will not turn at all. I was going to take the assy back but the big black cable that slides into the back of the housing will not release unless the key is in an "on" position. (1.) what is that cable, and (2) how the heck do I get that cable out if the key cylinder is jammed??? I am a newby so pardons around if I am breaking any rules but I really need some help. Thanks in advance.

 

The "big black cable" is the Park Lock cable that prevents the key from turning to LOCK unless the shifter is in PARK. If you cannot turn the key, you'll have to drill into the lock cylinder to separate it from the ignition switch first. You may want to call in an automotive locksmith. Depending on what went wrong, the locksmith may be able to undo it.