Speed sensor override via hidden screen

[jff]

There was a way on my 2004 LX470 to override the speed sensor by going into a hidden screen (one of the Nav screens had hidden buttons on it) and pressing/holding the Override button. Then I could use the full nav while driving, for example enter in a new address, etc. This is nice as usually I have a passenger who can do this while I drive, without it I have to pull over and stop to enter a new address even though my wife sitting next to me was perfectly capable of doing so. Anyone know how to do this (without changing anything physical, no cutting wires, etc. - just an override through the Nav that lasts until you turn off the car) on the LX570?

Regards,
Jason