This pertains to the nav system/clock in my 2003 TL.

99% of the time, I just use it as a clock.  And it displays, in nice
big numbers, the time.

But sometimes I need to check something on a map, get directions,
whatever, so I'll go to the nav system.  When that happens, the time
just shows up as a tiny number in the bottom right of the display.

My question is, how do I, if I no longer need the nav system readout,
make it just show the clock again, nice and big, on the display?  The
only way I can find is to turn the car off.  Fine, if mildly annoying,
while at a traffic signal, but ill-advised if on the open road or
expressway.