During my install, I couldn't find the speed wire on my 2007 Highlander, so I skipped it - leaving it unconnected.
Everything seems to work just fine.
What's the purpose of the vss speed wire?
_Am
Posted Jan 04, 2012 · 19:19 UTC#1
Purpose of the speedwire on z130bt?
Posted Jan 05, 2012 · 02:50 UTC#2
During my install, I couldn't find the speed wire on my 2007 Highlander, so I skipped it - leaving it unconnected.
Everything seems to work just fine.
What's the purpose of the vss speed wire?
_Am
As long as you always have GPS signal it doesn't serve a purpose. If you do lose GPS (tall buildings, tunnels, etc) the VSS is used in conjunction with the internal gyro and compass to perform dead reckoning navigation.
Posted Jan 05, 2012 · 03:13 UTC#3
The unit is 3D GPS and is always using the GPS, VSS/Backup wire signal plus accelerometer to do extremely accurate mapping. Look on here and you'll find people that didn't connect vss and backup wire saying the GPS isn't accurate which sorta makes sense if one of the signals is always saying the speed is 0.
Posted Apr 17, 2012 · 16:26 UTC#4
VSS is needed for dead rekoning and is used as a plausability check for the GPS.
Posted Apr 18, 2012 · 13:35 UTC#5
So you're saying not having the reverse signal is why my Navigation is always off a bit, and why it hasn't made any progress on 3D calibration? I thought the wire was only for the reverse camera. I haven't installed one yet, so I never connected the wire.The unit is 3D GPS and is always using the GPS, VSS/Backup wire signal plus accelerometer to do extremely accurate mapping. Look on here and you'll find people that didn't connect vss and backup wire saying the GPS isn't accurate which sorta makes sense if one of the signals is always saying the speed is 0.
Posted Apr 18, 2012 · 14:38 UTC#6
No, the backup signal is also used in conjunction with VSS and rotation sensor, to dead-recon compute all motion. Without a B/U signal, all VSS tics are interpreted by the HU as forward motion, which doubles the error. However, I also didn't install the B/U wire, and I don't think it changes much (unless you drive in reverse a lot). Once you get a good GPS fix, i doubt it matters.
Edited Apr 18, 2012 by RonS