Guess the mystery device (attached to windscreen)

[NGRhodes]

Came with my Previa (ACR30), it appears aftermarket, though my neighbour opposite also has a Previa with one in also, my guess is its the remains of some kind of antenna for an old sat nav or phone car kit.
Its definitely nothing to do with the factory radio or GPS.
I would take it apart to take a look inside, but its in an awkward spot to get.

[flash22]

Possible the aerial for the ETC tolls in Japan, Rain or Auto lights sensor

[PreviaBloke]

Finally, got it! It’s the 'RDS antenna' according to Toyota, an FM antenna for RDS-TMC (Radio Data System - Traffic Message Channel) or as Toyota calls it, ETA (Electronic Traffic Avoidance). It picks up traffic updates 24/7, which can be viewed in MENU > TRAFFIC INFO. The satnav uses the info as well for automatic or manual rerouting in order to avoid various traffic events. My Previa came with it in 2003 and has the TNS300ETA Radio/CD/Satnav. It was detached when the windscreen was replaced. So now it kinda just hangs there, but appears to work OK. The number of TMC messages received appears on the display next to the GPS satellite count. I presume the transparent strip of tape on the windscreen is part of it and the device's metal spring is supposed to be in contact with it.

 

More at:

https://media.toyota.co.uk/electronic-traffic-avoidance-available-now/

https://www.trafficguard.net/resources/blog/radio-data-system-traffic-message-channel