Power lock malfunctioning when shifting from P to D

I have no problems with power lock till today.
I parked the car for lunch without problems... when i start it to go to work in the afternoon, and shift gear from P to D, instead of locking the doors, nothing happens. Few seconds after, still in D, i hear some "click-click-click" noise, maybe 3 or 4 clicks, like the power lock tried to open or close the locks. Then, the present situation is:
-Shifting from P to D: door locks remains opened, no sound heared
-Shifting from D to P: door locks trying to "open" even if already in open position
-Pressing the lock buttons on the doors will operate regularly

I think there's something wrong, probably worn, in the shifting lever on the steering column, as ALL the others systems to operate the power locks (button and remote) function correctly.
Is there something to check before i start to disassemble half the car? PLEASE.

Here's the circuit for a 1996 Roadmaster Estate Wagon - Not sure what you have, but doubt there would be much variation across the years?

Probably the lock module. You can fix it if you can find the parts. If you can not find the parts, I have some on hand.

It seems that the thing started to work again. Probably it was some dirt over a contact, or some moisture (it's been raining for a week).
Anyway... i was assuming that the shift lever on the column has some electrical contacts on it, like a "switch" that operate the lock and unlock relays. In the diagram, indeed, i see a "Park/Neutral Position switch" that I think is the worn/dirty piece. It's easy to remove, and try to clean it?

The neutral switch is locate at the bottom of the column. It clips onto the top of the column, and has small detents to position it. It is fairly easy to remove, but a little difficult to get to.