GPS issues / errors
- Thread starter MCtree
- Start date
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- Thread starter
- #22
Sorry… I should have been more clear.
When they couldn’t fix it at the dealer, they escalated to Toyota.
So I think it was 5 world wide or maybe US wide.
Though to be clear, this is what the dealer told me. I’m not suggesting he was lying - just that I didn’t hear it first hand from Toyota. So things could have gotten jumbled.
I’ll call the number he gave me for Toyota tomorrow morning and give an update on what they tell me.
I worry they will try to say I voided the warranty or something by getting the aux battery installed.
- Thread starter
- #23
My map shows instantly too with a location (sometimes a block off).
But watch the three letters in the upper right corner of the screen “GPS.” Are they white as soon as you pull out of the garage? Or are they greyed out at first, while it finds a signal?
Have you heard anything else?
- Thread starter
- #25
After much discussion with both the dealer and Toyota, the foreman of the shop at the dealer agreed to connect an aux antenna to see if it was my antenna that’s the problem.
I didn’t get why they didn’t do this on either of my previous visits. They never gave me a good response to my questions on why they didn’t perform this test already.
But at least it’s progress instead of them just telling me I need to live with the problem.
But to run this test, they need to tear into my head unit. I have several upcoming road trips and I don’t love them digging into my LC like that right before I need to count on it starting each morning.
So we agreed that they would do the testing after June. I’ll bring it to them then.
I should also say that one of my upcoming trips is to drop the 200 off at Slee for them to add a rear bumper and an aux tank.
So I wanted to get it firmly and formally recorded with Toyota that I have this issues BEFORE I had the work done, lest they try to worm out of fixing it.
But I will certainly keep this thread updated as more goes on.
For what it’s worth, I drove from Houston to Mason a few weekends ago (5 hours north-west). For the first two hours of the trip, the nav showed me in the gulf half way to the Bahamas. Then it corrected itself.
But then driving around Houston in subsequent weeks it got wonky again.
I didn’t get why they didn’t do this on either of my previous visits. They never gave me a good response to my questions on why they didn’t perform this test already.
But at least it’s progress instead of them just telling me I need to live with the problem.
But to run this test, they need to tear into my head unit. I have several upcoming road trips and I don’t love them digging into my LC like that right before I need to count on it starting each morning.
So we agreed that they would do the testing after June. I’ll bring it to them then.
I should also say that one of my upcoming trips is to drop the 200 off at Slee for them to add a rear bumper and an aux tank.
So I wanted to get it firmly and formally recorded with Toyota that I have this issues BEFORE I had the work done, lest they try to worm out of fixing it.
But I will certainly keep this thread updated as more goes on.
For what it’s worth, I drove from Houston to Mason a few weekends ago (5 hours north-west). For the first two hours of the trip, the nav showed me in the gulf half way to the Bahamas. Then it corrected itself.
But then driving around Houston in subsequent weeks it got wonky again.
Thx for the update. Yeah, sometimes mine puts me in the Tennessee river. I am thinking of getting into the dash in the next few weeks myself and checking connections, cable management, and trying the aluminum foil wrap. Trim pieces should be relatively easy to pop off since the dealer has already been back there to install the Naviplus. Don't blame you for not wanting to rock the boat before a trip. Keep us posted.
- Thread starter
- #27
@gaijin,
Could it be that it’s much longer than 25 min? More like 45 to download all the necessary data?
I ask because after all my road trips this summer, my GPS was pretty solid for a while, even back here in Houston. But I haven’t gone anywhere in a bit and it’s starting to act wonky again.
I haven’t taken it back to Toyota yet because, like I said, it was good here in Houston for a few weeks upon my return.
So either there is an intermittent disconnect somewhere in the system that causes it to go awry or its that my GPS isn’t downloading the data correctly when I’m in Houston.
gaijin
GOLD Star
An ephemeris is valid for only four hours; an almanac is valid with little dilution of precision for up to two weeks.[7] The receiver uses the almanac to acquire a set of satellites based on stored time and location. As each satellite is acquired, its ephemeris is decoded so the satellite can be used for navigation.
The navigation message consists of 30-second frames 1,500 bits long, divided into five 6-second subframes of ten 30-bit words each. Each subframe has the GPS time in 6-second increments. Subframe 1 contains the GPS date (week number) and satellite clock correction information, satellite status and health. Subframes 2 and 3 together contain the transmitting satellite's ephemeris data. Subframes 4 and 5 contain page 1 through 25 of the 25-page almanac. The almanac is 15,000 bits long and takes 12.5 minutes to transmit.
GPS message format
| Sub- frame | Word | Description |
|---|---|---|
| 1 | 1–2 | Telemetry and handover words (TLM and HOW) |
| 3–10 | Satellite clock, GPS time relationship | |
| 2–3 | 1–2 | Telemetry and handover words (TLM and HOW) |
| 3–10 | Ephemeris (precise satellite orbit) | |
| 4–5 | 1–2 | Telemetry and handover words (TLM and HOW) |
| 3–10 | Almanac component (satellite network synopsis, error correction) |
Source: GPS Signals
So.. Nope. Looks like 12.5 minutes is all it takes for all the data to transmit - which means 25 minutes of uninterrupted reception of a good signal to assure successful download of the full 12.5 minutes.
HTH
Did you ever resolve this? Mine is doing something similar….
- Thread starter
- #30
Sorry. No.
I kept putting it aside and working on other things and eventually my LC was out of warranty.
Interestingly, this past weekend I went for a drive with my awning attached. My first long drive with the awing on.
And I felt that the GPS was even squirrelier than normal. Like somehow the folded up Kammok awning on the driver side roof rail was interfering with the antenna.
I’ll need to test this more to be conclusive though. Limited data so far……
I kept putting it aside and working on other things and eventually my LC was out of warranty.
Interestingly, this past weekend I went for a drive with my awning attached. My first long drive with the awing on.
And I felt that the GPS was even squirrelier than normal. Like somehow the folded up Kammok awning on the driver side roof rail was interfering with the antenna.
I’ll need to test this more to be conclusive though. Limited data so far……
Would hooking up one of these help the NAV systems's GPS?
- Thread starter
- #32
Where/how would you attach it?
Curious to hear who in here still uses the OEM head unit for regular daily GPS nav. I have installed beatsonic and use carplay now. Forgot the GPS in the head unit exists, but it is sometimes useful when out of cell bars and you forgot to download the maps to your phone. Anyway, do you guys still use it like for day-to-day drive, etc? I imagine the accuracy in terms of ETA and traffic must be abysmal in comparison to the modern live updates we get in our phones.
- Thread starter
- #35
Despite my LC gps often being wildly inaccurate due to some issue it has, I still use it when it’s working.
Since I still have the stock head unit, I can’t show my phone’s gps up there.
And I don’t mean to say that I use it to navigate. More, I use it for instant checks of location when I don’t feel like pulling my phone out. If that makes sense.
FrazzledHunter
SILVER Star
EDIT: see my post below which should have been here LOL! I must have fat fingered something.
Last edited:
FrazzledHunter
SILVER Star
I use the LC nav in "north up" zoomed out to city level for a birds eye view on long trips and Google maps in "track up" mode for turn by turn directions and live traffic info.
I can't remember the last time I keyed in a destination and actually used the LC's nav to actually navigate somewhere.
The lack of an app or some way to communicate with the nav system to upload and download destinations, routes, tracks, poi's, etc... like you can with a Garmin unit makes the entire LC nav stunningly useless, IMHO. That, coupled with the fact that map updates are on the order of $250 makes the LC's nav system a bit of a
abomination.
We ordered our Avalon specifically without Toyota's nav system precisely for this reason. To this day we use a Garmin nuvi clipped to an A/C vent. It's superior to anything from Toyota, again IMHO. Oh yeah, map updates are free from Garmin. It also works all of the time.
I can't remember the last time I keyed in a destination and actually used the LC's nav to actually navigate somewhere.
The lack of an app or some way to communicate with the nav system to upload and download destinations, routes, tracks, poi's, etc... like you can with a Garmin unit makes the entire LC nav stunningly useless, IMHO. That, coupled with the fact that map updates are on the order of $250 makes the LC's nav system a bit of a
abomination.We ordered our Avalon specifically without Toyota's nav system precisely for this reason. To this day we use a Garmin nuvi clipped to an A/C vent. It's superior to anything from Toyota, again IMHO. Oh yeah, map updates are free from Garmin. It also works all of the time.
