Just thought I would mention, a few weeks ago I went on vacation to the North Carolina coast and while there my family took a ferry ride from southport to fort fisher. While we were on the ferry, the NAV system never updated, it just showed us at the end of the ferry dock (the ferry was open air and the NAV antenna had a clear view of the sky). The NAV system did not update until we started to move, driving off the ferry at fort fisher. I thought this was interesting, and again I would guess showes the importance of the speed sensing wire attached to the NAV unit itself. Anyone with a idea as to why this took place, I would welcome you input...

 

My NAV system had a little trouble in North Carolina as well. It did not list duck or corolla as towns in the outerbanks. I had to use kitty hawk as a destination. Maybe it's a NC thing????

 

I have the same issue, on all ferries. LExus says it is normal.

 

You actually answered your own question. The nav position needs to see vehicle speed as well as the gps signals. If you drive a car without the speed signal input to the nav ecu, it will be very slow to update using just gps signals. Seen it before.

DD

 

yea it doesnt update untill it actully gets a speed reading