93 Grand Am strange auto lock problem

Hello :) I've got a strange question that I'll try to explain. It's a 3.3 V6, transmission has about 65k miles on it now and the torque converter is new as of 1/07. What I'm wondering is what causes the car to auto lock when put into gear?

Sometimes, when the car is started up, the little orange light next to the P on the gear shift isn't lit up. Today I noticed, while in park with all the lights off, that if I tapped on that light on the gear shift it came on. Also, at the same time, the car started to idle differently, which was very odd. Everytime I tapped on it and when the light would come on or go off, the idling would change. Then, at one point, I think when it lit up, the doors locked. I posted before about other problems I had with the car stalling, which I think my mechanic narrowed down to the MAF sensor, but this new strange problem makes me wonder.

I do notice sometimes it doesn't lock right when I put it in drive and not until a little bit after I've started going. Or it will lock itself while I'm still in park and letting the car warm up, when it sounds like it's "idling differently" - don't know another way to describe that.

Any info on what causes the car to auto lock and if it's transmission related, or something with some other sensor like a throttle position sensor or crankshaft sensor, or one of the other things besides the MAF sensor that is causing my car to stall.

Thanks very much everyone for any info you can give and for what I've been given already. :)

It should auto-lock when the gear shifter is moved out of park. Check the connector and wiring for the PRNDL switch. I think there is another switch near the gear shifter that affects it (I forgot to plug one back in once) but I don't remember what it did, it's been a long time since I did it. I think it disabled auto-lock when out of park, and went to auto-locking once vehicle speed is 5(?) MPH.

My 95 locked at 5mph, but it was a manual transmission. I had a friend with a 98 auto, that locked as soon as you put it in gear. Not too sure if that was the same for the earlier cars though.

All M/Ts lock when a speed is reached (usually 5mph), and when gearshift input isn't present A/Ts will lock for vehicle speed.

If I remember right you can program this to lock when you start the car, when its put into gear or when you reach 5mph or more. Thats the way my 93 GA was, and I think the newest ones are close to the same functions.

If it's below freezing, and just started not lock properly, it could be cold rretarded.
But checking the plug in the console might not hurt.
It shouldnt effect idle at all other then a voltage spike/drop when activated.

Your stalling could be several things at this point, granted it only has 65k miles but the wires and car is 15 years old, and they can dry rott and crack causing problems.

Hope that helps.