Here's what's inside an automatic transmission shifter and how it works:

The shifter mechanism removed from the car. Its purpose is to:
1. Select what gear/direction the transmission should be in.
2. Protect the transmission from misshifts.
3. Prevent roll-away.
This one has park, reverse, neutral, drive and a "S" mode which allows for manual up/down forward gear selection.

This is the side where we can see both limit switches to change forward gears:


On the driver's side, we see the solenoid (operates with ignition power), key interlock (prevent removal if not in park), shift lock relay and cam-mechanisms that control lockout.


Inside the shift lock relay:



A limit switch at the bottom of the shift lever near its pivot tells the computer the selector is in park.



Here we can see the track guide that allows shifting from P to D, and then over to S:



This is what's left of the shell:



The lever itself has a double pivot point, up and down for P to D, and sideways from D to S:



The shift interlock solenoid activates a rod that allows the gear selector to unlock when the brake is depressed and the ignition is on:



And that's pretty much all the components!



Enjoy!

 

Another awesome infomercial from 'Da Man!!

You sir are one of my modern day auto heroes, thanks for posting this.