Mobile phone signals

[Buckman]

My satnav picked up a new 40 mph speed limit imposed because of long term road works on the A350 it also had no problem picking up changing speed limits on the M6 when congestion control kicked in. But even with the latest mapping update it still thinks a local urban road is 60 mph when it has been 30 mph for aeons.

My TomTom shows the correct speed, but car is telling me I am in a 30mph zone when it is actually 60mph zone. I have tried to why, but no one on either Lexus or Toyota forums knows how the car decides that it is a 30mph zone when there are no road signs etc.

The Satnav in the Yaris can be either Google maps or Waze as it connects to the Smartphone and it shows the correct speed, but car indicates you are speeding when you are not speeding!

Obviously the in car is not using the Satnav signal and unlikely to be using mobile masts for correlate the position of the car. Signal in our area is generally one bar if you are lucky.

 

[Buckman]

My satnav picked up a new 40 mph speed limit imposed because of long term road works on the A350 it also had no problem picking up changing speed limits on the M6 when congestion control kicked in. But even with the latest mapping update it still thinks a local urban road is 60 mph when it has been 30 mph for aeons.

I have emailed the Lexus dealer asking about this issue and mentioned that you have the same issue with your new RAV4. The reply coudl eb interesting as I also mentioned that this morning we used the Satnav in the car which showed a 60mph zone, but car was stating it was a 30mph zone. On travelling through the 30mph zone in Droitwich car is telling us it is a 15mph zone, but Satnav had it at 30mph zone. BTW never ever come across at 15mph zone except on campsites.

 

[ProfJohnL]

It used to be a common quote, that as soon as you purchased a map book it would be out of date, simply becasue such books cannot update when a road system is changed after its been published.

With most satnavs, you can at least get updates, but even so where the map is held in the satnavs memory or on an SD card, again its going to be a snap shot of the map which wont dynamically up date.

Services such as Google Maps and Waze, are held in the "cloud" and are updated far more frequently, so you are far more likely to have up to date mapping when using these types of services. But even so they can still lag by a few weeks when for example speed limits are changed.

More specifically in relation to the display of incorrect speed limits, on Garmin and Tom tom satnav's is when traveling on a high speed road the sat nave will alert me to a lower speed limit, and it coincides with a local lower speed road that is bridged across the road I'm travelling on. The sat nav is obviously picking up on the lower speed limit of the local road.

I can't explain why a 90mph limit would be shown anywhere in the UK. Was it perhaps showing a Km/h speed?

 

[Buckman]

There is a difference between a car Satnav where in many cases you need to pay the dealer a fee to update it and a stand alone Satnav like the TomTom that continuously updates i.e. your route is blocked at some point several miles ahead. The Satnav offers an alternative route. Not sure of Google Maps or Waze offer this? Our TomTom has never had the issue of picking up a lower speed limit on an adjoining or close by road as that road is not on its route.

 

[otherclive]

There is a difference between a car Satnav where in many cases you need to pay the dealer a fee to update it and a stand alone Satnav like the TomTom that continuously updates i.e. your route is blocked at some point several miles ahead. The Satnav offers an alternative route. Not sure of Google Maps or Waze offer this? Our TomTom has never had the issue of picking up a lower speed limit on an adjoining or close by road as that road is not on its route.

My car satnav updates continuously during a journey giving me traffic conditions and options for a detour if I require. But as far as database and map updates are concerned Toyota issue two updates a year. So if you pay a fee you get 12 months usage with two updates. After that no more updating of the maps. You can download updates from the Toyota website via a USB stick, or over the air. But the latter is slow.

 

[Buckman]

My car satnav updates continuously during a journey giving me traffic conditions and options for a detour if I require. But as far as database and map updates are concerned Toyota issue two updates a year. So if you pay a fee you get 12 months usage with two updates. After that no more updating of the maps. You can download updates from the Toyota website via a USB stick, or over the air. But the latter is slow.

I have hardly used the car Satnav since purchase and today was one of those occasions. I did notice that there was an option to select a traffic option, but never bothered. I must get around to looking at it again. Manual states "
Traffic messages such as traffic congestion, accidents and road closures are displayed on the map or the list. Traffic data can be received via radio broadcast or internet. A quick read shows that the car Satnav offers quite a lot of info.

 

[Tobes]

There is a difference between a car Satnav where in many cases you need to pay the dealer a fee to update it and a stand alone Satnav like the TomTom that continuously updates i.e. your route is blocked at some point several miles ahead. The Satnav offers an alternative route. Not sure of Google Maps or Waze offer this? Our TomTom has never had the issue of picking up a lower speed limit on an adjoining or close by road as that road is not on its route.

Yes, some car satnavs can route round traffic and closed roads. Yes Google and Apple and Waze do this too. Yes some car manufacturers make you pay for updates. Yes some are free, and some happen over the air without you noticing.

 

[RogerL]

Interesting Clive. Just proves how hit and miss phone signals are

Fred Drift

The VW is the worst I've had. It chooses routes that are ridiculously stupid.
VW want £800 to update 😡
So thinking about Waze on the i phone or a state of the art Tom Tom.
The Waze uses phone signals. The Tom Tom satellites.
Which overall is my best bet??

Waze has an issue that it can't select a route at the start of a journey if it can't connect to the internet using the phone - so necessary to start the journey using brain and atlas and then stop to plan the route when a signal can be obtained.

Is that £800 just for the dealer to update the onboard sat nav software and firmware ? The final update for mk2 Touareg (up to 2018) was issued in 2023 with no more updates available - I got my 2023 update from an ebay seller for £53 but it can be done FOC if you're good with technology.

A more cost-effective update for the Touareg is a Kremer box for around £500 which provides CarPlay and Android Auto