2002 Monte Carlo will not turn to off position and acc always on and the battery dies. What is going on?

No, sounds more like an ignition switch problem, but not ruling out your thought. If the shift cable is out of adjustment, the car may 'think' it's still in gear and won't allow the key to be turned off. But are you able to pull key out or is it stuck in switch? Automatic..right?

Yes the key will come out but power still on for accessories. That makes the battery go down. On this model where would the shift cable come from that enters back of switch?

Automatic console shift and ignition switch on dash.

Did not answer the question where is the cable originate from that enters the back of ignition switch this is preventing the ignition from going to off when you turn the switch? normal operation is when you turn the switch on..it unlocks transaxle cable.

Guess I will just get a new ignition switch and go from there.. Duo

getting a new switch will not help I had same problem I just unplug the cable & left it unplug then the key will go to off fully don't know the long term result yet

WD-40 JUST SAVED ME $140 SPRAYED IT KEY HOLE AND WORKED IT BACK AND FORTH AND ON AND OFF TILL IT WENT OFF IT WORKED FOR ME

I've had that issue to I just pulled the cable out and left it now I'm really having an issue the key goes completely to the off position and all my lights and some times the it would act as if the key was fully on and then just go back to just the lights being on no extra wires connected anywhere it started fine after I hooked my radio up then I went to start it up to move it a few mins later and it wouldn't start and lights won't shut off with key out