I’ve just taken delivery of my 2006 Alphard v6
It has what looks like a telescopic aerial on the wing.It is activated by the Pole switch.
I asked Jap Autos what it was for .He said it was a parking aid.
I,m still investigating
An interesting source I’ve found is an Indonesian blogger
“8seaterblogger .com”
Hes helped me no end with my head unit.
hope this helps