I have had this problem happen 3 times. It tells me I am in Los Angeles, right by HWY 101/Hollywood Freeway and keeps me there. This happened 1 time after I haven't driven the car for a few days and when I drive it keeps me positioned in the same spot, and doesnt move the position, but recognizes when I turn my turning the marker. The last time it happened, I was driving on the highway, had directions being displayed and was in route. All of a sudden it jumped me to the SAME location in Los Angeles, and doesnt move at all when I drive. Then last time I was in SF, CA, and I was driving down market street. I keyed in return home, it started to calculate route, and then brought me back to the SAME location in Los Angeles, and did the same thing until I reset it. Driving around, waiting for GPS to "re-see" my position doesn't work either as I have driven for 30 minutes and it never moves me from that one spot in LA until I reset the unit.

Any ideas? I am using the Bypass and have no VSS hooked up.

Did you check the gps reception when you had this problem? Sounds like the unnit isn't getting a good gps lock and without a vss signal the unit has no idea that the vehicle is moving forward.

Yes only one GPS satellite was not showing, the first time, and all where present the second time. VSS should have nothing to do with the positioning, as my D2 was hooked up for 5 months with no issues.

ANYbody have any ideas, I am almost ready to take this back to Best Buy, and exchange, but they do not have any in stock, so I may be w/o a head unit for a week or 2.....

Happened to my D3 once before, I hooked up my VSS after that and modified my current location to where I really was. Has been dead-on accurate since so one of the two solved the problem. I too had a D1 for years with no VSS and no problems, so maybe the D3 is more tempermental than the D1/2 when it comes to VSS connection

Talked to the very helpful Pioneer Tech support..... they kept blaming it on my antenna, even though I have all but 1 bar active most of the time. Finally after explaining that I have all bars, he said it was most likely a defective unit, to do an over the counter exchange since I am under the 30 day mark.