GPS Positioning problem
09-15-06, 11:11 PM
#46
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Man I am telling you right now, if your dealership is acting up and being an *** you should call or threaten to call lexus headquarter. When i bought my car, the salesman noticed that the finance people didn't treat me very well and he took me outside and told me not to tell lexus headquarters, as a reward he gave me BIG BIG discount on services and products. I think they'll get in trouble if customers complaint and not many customers now this. Competition is tough out there
since i last posted the problem i have been to the dealer 2x and both times they claimed it was fixed but as i drove home the nav began to stray off course. i am finally scheduled to bring in the car again tomorrow but they are hesitant in giving me a loner car despite the fact that the car obviously needed more than one day with a grease monkey. anyone know the protocal on loner cars?
i bought a lexus based on the looks of this IS and the reputation of quality of service was undeniably a factor in my decision. unfortunately, my dealer has NOT been very helpful nor has lexus customer service which responded to my complaint via email 2 weeks after i emailed them of my complaint. even the response was awful...(paraphrase) "we will investigate and a representative will contact you in 3 - 5 business days"...i'm still waiting lexus?
about 2 years ago mercedes was having problems with the E-class electronics. I forgot the specifics of the electronics problem but I recall mercedes replacing the cars of those that were affected. thats great customer service...i cant even get a freakin' call back from these guys, what gives?
it is also quite apparent that i am not the only one facing this problem. if anyone has further info on this matter please help with a reply. i am hopeful of my 3rd visit to the shop. i hope the knuckleheads will finally listen to the fact that recalibrating/"rebooting" is not the answer to the problem. i believe its the hardware...the antenna? or it can be that cpu someone mentioned earlier.
AAAAAAAHHHHHHHHHH!!!!
-mike
i bought a lexus based on the looks of this IS and the reputation of quality of service was undeniably a factor in my decision. unfortunately, my dealer has NOT been very helpful nor has lexus customer service which responded to my complaint via email 2 weeks after i emailed them of my complaint. even the response was awful...(paraphrase) "we will investigate and a representative will contact you in 3 - 5 business days"...i'm still waiting lexus?
about 2 years ago mercedes was having problems with the E-class electronics. I forgot the specifics of the electronics problem but I recall mercedes replacing the cars of those that were affected. thats great customer service...i cant even get a freakin' call back from these guys, what gives?
it is also quite apparent that i am not the only one facing this problem. if anyone has further info on this matter please help with a reply. i am hopeful of my 3rd visit to the shop. i hope the knuckleheads will finally listen to the fact that recalibrating/"rebooting" is not the answer to the problem. i believe its the hardware...the antenna? or it can be that cpu someone mentioned earlier.
AAAAAAAHHHHHHHHHH!!!!
-mike
09-17-06, 07:39 AM
#47
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Anything less than 3, and your SOL and the system just works on speed sensor input and perhaps a steering sensor / gyroscope. It's pretty accurate in tunnels, but if you do any significant turns without a satellite signal, it'll lose you quickly.
09-18-06, 05:47 PM
#48
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I have had my car in 6 times now, they have replaced the disc, the nav "brain", and broke my mirror off the window. My nav still doesnt work. They showed me where to check the list of satellites and told me to look at that whenever it messes up. It is always connected to 5-7 satellites when screwing up. My dealer did tell me the antenna is located in the back window. Any idea if that is true???
09-18-06, 06:40 PM
#49
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09-18-06, 06:41 PM
#50
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Yeah, what he said.
Last edited by lobuxracer; 09-18-06 at 06:42 PM. Reason: Me Too Answer
09-19-06, 06:08 AM
#51
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In my case, as soon as I see four birds with a "P" status, I have GPS lock.
(Also, for some unknown reason, my GPS system seems to be improving. I'm getting a lock about 3/4 of the time now)
09-19-06, 08:15 AM
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The dealer's been working on my car since thursday and still no word...i aksed about the CPU for the NAV that someone mentioned earlier and my customer service rep laughed and said there is no such thing. its quite obvious that they have no clue whats wrong with it.
regarding my car being a lemon...since i paid extra for the nav system wouldnt the defective nav be enough to considered the value of the car impaired?
regarding my car being a lemon...since i paid extra for the nav system wouldnt the defective nav be enough to considered the value of the car impaired?
09-19-06, 08:19 AM
#53
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I have had my car in 6 times now, they have replaced the disc, the nav "brain", and broke my mirror off the window. My nav still doesnt work. They showed me where to check the list of satellites and told me to look at that whenever it messes up. It is always connected to 5-7 satellites when screwing up. My dealer did tell me the antenna is located in the back window. Any idea if that is true???
09-19-06, 08:48 AM
#54
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Just because you see the satellites listed on the diagnostic screen doesn't mean that the nav is getting a clean signal from them. Did the dealer tell you to check the signal and status columns? I look for satellites to have a status of "P". I believe the ones where the status is blank or "T" are not getting a usable signal.
In my case, as soon as I see four birds with a "P" status, I have GPS lock.
(Also, for some unknown reason, my GPS system seems to be improving. I'm getting a lock about 3/4 of the time now)
In my case, as soon as I see four birds with a "P" status, I have GPS lock.
(Also, for some unknown reason, my GPS system seems to be improving. I'm getting a lock about 3/4 of the time now)
shouldnt the gps get a lock 99.9993% of the time?
09-19-06, 10:16 AM
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Count me in on this problem now too. Only happened 2 times. The first time I don't remember the details of the day (how hot, where i was, etc)... but the second time was recently. Driving thru Boston, 65 degree night, car parked in a parking garage out of the sun all day. System showed me being about 4 streets over from where I actually was. Could it be the buildings interfering with the signal? I know this isn't the cause for everyone's problem, but could it be the cause of mine for this one instance?
09-19-06, 12:02 PM
#56
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my car seems usually has 5-7 satellites with a "P" next to them. Other than that there seems to be 2 that occasionally show a "T". I drove home yesterday (25miles) with that screen on the whole time and saw it drop twice to no signal from any satellite and about 10 seconds at a time. It happened on open road, no overpasses / tunnels, and no trees either. Suddenly all the satellites would come back. weird.
09-19-06, 03:58 PM
#57
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The dealer's been working on my car since thursday and still no word...i aksed about the CPU for the NAV that someone mentioned earlier and my customer service rep laughed and said there is no such thing. its quite obvious that they have no clue whats wrong with it.
regarding my car being a lemon...since i paid extra for the nav system wouldnt the defective nav be enough to considered the value of the car impaired?
regarding my car being a lemon...since i paid extra for the nav system wouldnt the defective nav be enough to considered the value of the car impaired?
09-19-06, 10:48 PM
#58
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my car seems usually has 5-7 satellites with a "P" next to them. Other than that there seems to be 2 that occasionally show a "T". I drove home yesterday (25miles) with that screen on the whole time and saw it drop twice to no signal from any satellite and about 10 seconds at a time. It happened on open road, no overpasses / tunnels, and no trees either. Suddenly all the satellites would come back. weird.
I had a mystery problem with my Supra that ended up being a single pin on the ECM connector that would only connect when the cabin temperature was more than 55F. It took the better part of a very cold day to determine exactly where the problem was. I was ready to tear my hair out trying to find the fault too.
If we have a poorly built, poorly chosen, or poorly designed connection to the satellite receiver/amplifier, it would explain these intermittent problems and possibly the thermal aspect of the problem as well. It doesn't explain how you could have 5 - 7 birds in sight with lock and drift off though.
09-25-06, 03:25 PM
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Jamming Issues
Hi Guys,
Just posting my .02. As an employee of a GPS chipset manufacturer, I can tell you anything you need to know about GPS.
I'd be willing to wager this is a jamming issue from some electronics close to the GPS antenna/module. A car is a very noisy place especially one jam-packed with electronics like the Lexus. It's also possible the antenna is sub-optimal or the connector is loose or the GPS receiver isn't properly shielded. In-band jamming, would explain a lot of the issues you guys are seeing (long cold-starts, position jumps, etc). Radar detectors, metalic tint and even cell-phone modems can cause interference issues. LCDs are also a notorious source for GPS jamming.
I can say with strong confidence this isn't a heat issue. Unless, I am wrong here, most of the Japanese auto mfg's use a Nippon company called Furuno (you might be familiar with their fish-finder consumer products). In any case, the Furuno receiver is spec'd to the automotive temp. operating range of -40 to +85C. That's right celsius. I doubt any of you operating your vehicles anywhere close to the maximum ratings.
Just posting my .02. As an employee of a GPS chipset manufacturer, I can tell you anything you need to know about GPS.
I'd be willing to wager this is a jamming issue from some electronics close to the GPS antenna/module. A car is a very noisy place especially one jam-packed with electronics like the Lexus. It's also possible the antenna is sub-optimal or the connector is loose or the GPS receiver isn't properly shielded. In-band jamming, would explain a lot of the issues you guys are seeing (long cold-starts, position jumps, etc). Radar detectors, metalic tint and even cell-phone modems can cause interference issues. LCDs are also a notorious source for GPS jamming.
I can say with strong confidence this isn't a heat issue. Unless, I am wrong here, most of the Japanese auto mfg's use a Nippon company called Furuno (you might be familiar with their fish-finder consumer products). In any case, the Furuno receiver is spec'd to the automotive temp. operating range of -40 to +85C. That's right celsius. I doubt any of you operating your vehicles anywhere close to the maximum ratings.
09-25-06, 03:36 PM
#60
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So the coincidence of bad positioning and 150+F temps inside the car are purely coincidental?
Why would it self-correct as the interior temperature drops?
Is there a local oscillator or a passive component that could be heat affected?
I agree about the chips, they are generally pretty good at temperature. Quartz crystals are not as good. The ones I had in my Cesium and Rubidium clocks were wrapped in thermal blankets to maintain a very constant temperature and minimize drift. Any chance this might be happening here enough to lose lock on a satellite?
Also, on a Google, I'm finding two levels of permissible thermal range - one is -20 to +70C, the other is -40 to +85C. I have no trouble believing the dashboard gets up to +70C when it's +42C outside as it was here in Sacramento last summer.
Why would it self-correct as the interior temperature drops?
Is there a local oscillator or a passive component that could be heat affected?
I agree about the chips, they are generally pretty good at temperature. Quartz crystals are not as good. The ones I had in my Cesium and Rubidium clocks were wrapped in thermal blankets to maintain a very constant temperature and minimize drift. Any chance this might be happening here enough to lose lock on a satellite?
Also, on a Google, I'm finding two levels of permissible thermal range - one is -20 to +70C, the other is -40 to +85C. I have no trouble believing the dashboard gets up to +70C when it's +42C outside as it was here in Sacramento last summer.
Last edited by lobuxracer; 09-25-06 at 04:05 PM.