[NJ H2]

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NJ H2 - I'm not quite sure what your reffering to, but FYI Garmin is about to release a street pilot GPS that has dead reckoning capability. As I have never had any GPS yet I am not sure how important this is. It seems like a lot of extra hook ups to attach if its not part of a gps intergrated into the dash. I'm also not sure if dead reckoning would work off road where direction changes may be frequent and subtle, as opposed to city driving where you will more often make 90° turns.<HR></BLOCKQUOTE>

VSS (Vehicle Speed Sensor) Hooks to the The Transfer Case Module and to the back of the DVD NAV. It will keep you on track even if you have no signal from the Satellites, by telling the NAV how fast you are going and if you go in reverse. Basically, it keeps you on track in conjunction with the Satellites.
As for showing your position off road it does on my ML, and I would guess this 1 would also.