My 02 SC430 did it twice today for the first time. After multiple re-starts it finally came out. Ever determine the cause? Thanks

 

My 2007 GX470 would not shift so I had to replace the transmission cable bushing ($15 part on Amazon). When I reassembled the gear shift assembly (black plastic box), and shifted into PARK, I noticed that I could not turn the key fully left to the LOCK position and the key would not come out of the ignition. The key only stayed at the ACC position. If I disconnected the battery, the key would turn all the way left to LOCK and I could remove the key.

The problem was that I accidentally knocked lose a tiny spring switch located on a PC board inside of the white plastic assembly that is to the inside left of the black gear shift assembly box. This is the same white plastic box the shift interlock release pin goes into. The shift interlock release pin is white plastic and has a coil spring at its base. The bottom is pointy and the top is square and rests inside of the top of the black shift assembly box.

See the photos below - the tiny spring switch has a blue plastic square base with 4 tiny legs that each have one hole in them. The top is a stainless steel thin band that is shaped curvy. This switch activates the lock in the ignition cylinder that prevents you being able to turn the key to the left into the LOCK position unless the shifter is in park. When installed, and you depress the stainless steel spring band, you can hear a small clicking inside the ignition cylinder and the key will easily move to LOCK and let you pull it out.

PS - make sure that the stainless steel curved band is bent far enough towards the shift shaft so that the shaft engages the switch when in Park. My photos were taken before I bent the spring band further towards the shift shaft.