2012 LR4 GPS showing me 150 miles away....

[Dicky Doyle]

Hey all, I have searched for several days now with 0 luck so, hopefully I didn't miss something here. This past weekend I noticed my onscreen nav was showing me in Hinton, WV and I live in E. Tenn. As I drive the map moves, but it will not default to where I actually am. The GPS and TMC icons on the display have a red line through them. I'm not sure if the "shark fin" antenna on top of the vehicle is the antenna for the gps, it only has one yellow wire coming inside the vehicle from it, and when I unplug it, I have no satellite radio service, so I am assuming the antenna isn't the issue, unless this isn't the gps antenna. Does anybody know where the Nav unit is located in this model so I can find it and check the connections to it? And also, if the shark fin antenna is in fact not the gps antenna, does anyone know where it is located. I will try attaching a couple photos I took of the screen. Thanks in advance for any and all help.

 

[joey]

Not sure if it effects you that far south, but I do know that are doing GPS interference testing from the 9th to the 20th in southern Indiana (it does show going down as far as Tennessee so not sure) If after the 20th it is still an issue then I would have it checked. And yes the fin is the GPS antenna.

 

[Dicky Doyle]

Not sure if it effects you that far south, but I do know that are doing GPS interference testing from the 9th to the 20th in southern Indiana (it does show going down as far as Tennessee so not sure) If after the 20th it is still an issue then I would have it checked. And yes the fin is the GPS antenna.

Thanks for the reply. As of this morning I'm still having the issue. I talked to service at LR Knoxville and they said it was either antenna or needs reset/updated. If its antenna they quoted me $600 because the antenna is inside the roof and only accessible through the third brake light on roof and it has to be removed at a glass shop because it is glued in. I ordered a gps antenna with the same connector as the LR antenna has to test that. I was told by a friend at a car audio shop that any gps antenna should work as long as it has the correct connector. A reset/update is $120 plus tax. But I'm hoping this $10 antenna fixes it. Only thing that worries me about it though is I can unplug the antenna and nothing changes.

 

[joey]

If you can unplug the antenna I doubt it is the antenna that is bad. I am sure it can happen, but I have never seen a GPS antenna that works go bad, unless of course it has been seriously knocked around, then maybe.

 

[Dicky Doyle]

If you can unplug the antenna I doubt it is the antenna that is bad. I am sure it can happen, but I have never seen a GPS antenna that works go bad, unless of course it has been seriously knocked around, then maybe.

This one cant get knocked around, it is actually "inside" the roof. If you lift upper tailgate there is a piece of trim that runs along the top of the glass you can snap off, that is where the antenna plug is, and you can look back through a small hole and see the side of the antenna. LR service told me the shark fin antenna is satellite only. I'm just kinda confused as to why the map still moves as I drive, just showing wrong position, even with the antenna unplugged. I'm kinda leaning toward a software issue that needs to be reset/update.

 

[joey]

If you have unplugged the antenna from a GPS unit how in the world is it getting satellite links? I am not sure this is possible. I know for a fact this doesn't work in my airplane. If I unplug the GPS antenna it doesn't work.

 

[Dicky Doyle]

If you have unplugged the antenna from a GPS unit how in the world is it getting satellite links? I am not sure this is possible. I know for a fact this doesn't work in my airplane. If I unplug the GPS antenna it doesn't work.

Exactly...I'm not sure how it works...but I unplugged it it and drove down the road a few miles and the map moved on the gps like it was tracking my movement. Who knows lol

 

[TheWidup]

I've noticed that I see movement without a gps signal in the Chicago underground. I think somebody spent a ton of resources to have the computer calculate movement plus direction from the compass to cover when the gps signal fails. That's probably why you're seeing movement with no signal.

 

[Dicky Doyle]

I've noticed that I see movement without a gps signal in the Chicago underground. I think somebody spent a ton of resources to have the computer calculate movement plus direction from the compass to cover when the gps signal fails. That's probably why you're seeing movement with no signal.

I'm hoping this antenna I ordered from Amazon fixes it. I was told that the only real difference in gps antennas are the connectors, and I found the right one for $10.50, had $9.01 reward credits so it cost me $1.49 lol. If this antenna doesn't fix it maybe it just needs updated/reset, that would be $120....sure beats $600 tho.

 

[Dicky Doyle]

Antenna from Amazon fixed my gps, only issue now is the TMC button still has the red line through it. I've read that you need to tune to a fm station that broadcasts the tmc signal and leave it on it for a couple hours. I cant find any info of local stations in my area that broadcast it. I'm just wondering if the TMC function is also controlled by the factory gps antenna. I think I read somewhere that the "receiver" for the tmc is on the main ecu. Anyone have any info on this issue?