AVIC-N1 Speed inaccuracy

Printed From: the12volt.com
Forum Name: Mobile Video, GPS, and Navigation
Forum Discription: Mobile Video Head Units, DVD Players, LCD and TFT Monitors, Navigation, GPS, PS2, PS3, XBox, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=44147
Printed Date: May 12, 2025 at 9:56 PM

Topic: AVIC-N1 Speed inaccuracy

Posted By: ichabodsteel
Subject: AVIC-N1 Speed inaccuracy
Date Posted: November 30, 2004 at 4:16 PM

Anyone out there notice speed inaccuracies with the Pioneer AVIC-N1? Mine is installed on a 2004 Toyota Sienna and VSS is tapped into the factory wiring (in dash) for the Navigation and the AVIC is showing about 4-5 MPH slower at highway speeds and affecting the accuracy of the indication on the Nav.

Its connected to the Violet/White VSS cable. Any Help/comments would be appreciated.

Replies:

Posted By: meltingplastic
Date Posted: November 30, 2004 at 4:50 PM

i dont have my vss hooked up and my speed is dead on..

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Driving a Bagged, Caddied 02 s10

Posted By: ichabodsteel
Date Posted: November 30, 2004 at 6:59 PM

Thanks for the info. That's something easy to test.

Posted By: jeremyjerm
Date Posted: December 01, 2004 at 10:02 AM

it varys from car to car. ive noticed GMs will usually be dead on. but ive done a few imports n they were 5 mph off at the most

Posted By: ichabodsteel
Date Posted: December 01, 2004 at 12:49 PM

Tried to disconnect the VSS last night and became worse on the Sienna. So, I reconnected it and tried experimenting to move the GPS unit from inside the dash to under the seat and hoping that the more secured mounting may help??? I finished after midnight and haven't driven the car around enough to get the vehicle statistics to activate yet. Keeping my fingers crossed...

Posted By: meltingplastic
Date Posted: December 01, 2004 at 6:04 PM

easy solution.. buy a gm lol.. good luck man.. if u figure it out post.. would be nice to know incase i run into that problem

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Driving a Bagged, Caddied 02 s10

Posted By: ichabodsteel
Date Posted: December 06, 2004 at 10:50 AM

The new location hasn't fixed it yet. But I wonder what that 3D and speed and turning learning function is supposed to do??? If it always knows that I'm turning before an intersection and self corrects, wouldn't you think the software programmer could determine a compensation to fix this inaccuracy? Otherwise, what is all that learning function for? What version map are you guys on? I'm on v1.2 - 2nd free replacement. Well, once the learning is complete, I'll post the speed accuracy result once again.

By the way, when I called Pioneer, they said if I connected the wire properly/securely, it should be dead on. I called a local installer and he said they connect it directly to the transmission, but to me its all the same wire. Besides, when I check the connection status, it is getting the signal..... I guess I'll have to live with the difference. Will consider different NAV next time...

Posted By: elbe
Date Posted: January 06, 2005 at 10:25 AM

Most vehicle speedometers are optimistic and up to a max 10% variation can be observed. According to law, the variation must be on the slow side. It also depends upon the tire and rim sizes you have installed.