OT - Satnav very confused

Time to switch to Apple Carplay?

Low battery voltage from a failing battery can do this

The battery is brand new.

I just checked again after having left the car for a few hours. The satnav was still showing the French location (evidently saved from last time). However, when I asked it to report its present location it accurately reported where it was, and when I returned to the map display that was now correct.

Is is very strange that it thought it was over 400 miles away. It was a little foggy this morning, but not enough to interfere with a satnav signal.

Android phone here. I didn't think of asking that to display the location while I was sitting in the car. Too late now, unfortunately.

Could some nefarious mob be jamming the GPS signal?

Lot of strange s*it going on in satnav land. As also in flight radar where some jets flying out of US airbases do not show up on flight radar etc.

Anyone would think there was a war on...

Yes indeed - and the OP was fairly close to Southampton Airport when the problem occurred.

Yes.

Local 'interference' knocks out everything

A few years ago we drove around various south-easterly bits of Australia. Our TomTom satnav unit worked well except that it got totally confused in several blocks near the centre of Canberra. I later worked out from a real map that we were rather close to the US Embassy. I'm pretty sure that they were operating a jamming signal. These things may become more common, unfortunately.

GPS is sometimes confused close to Buckingham Palace.

John

It sounds as though it went out and had a few glasses of French wine last night.

When we first got our present car, which has built-in satnav with data provided (I think) by Garmin, it would occasionally take a couple of minutes to find its location when I first set off. That was in a rural setting, so not enclosed city streets that may block the view of some satellites. It hasn't done that for ages, but it used to be every few months.

My first Samsung Android smartphone, from about 2012, had problems with its GPS. It would randomly set itself to a location somewhere near the equator in Africa. It still recorded relative movement perfectly, but translated by many thousands of miles. I remember working out that it was a constant error (for any given day) of so-many degrees longitude and latitude but I've forgotten what the offsets typically were, and they were slightly different on each occasion that it happened. It was rather disconcerting (!!) to be going for a walk, checking my position on an OS map displayed by Viewranger, and suddenly seeing a blank background because my reported position was off the map. Rebooting the phone usually fixed it.

Even now, it's quite common to see constant offsets of a few tens of metres: a track that is following a road on an OS map suddenly jumps a bit to one side and still follows the twists in the road, but with an offset. Then it fixes itself. I wonder what error in the satellite signals that it receives can cause constant offsets, as opposed to random errors either side of the true position.

When it works, GPS really is fantastic. The "you are here" mark on an OS map is invaluable when trying to follow a path on the ground which disappears. All you need to do is to walk on what looks as if it might be the path, and see where your marker goes - and if it doesn't follow the footpath track on the map, turn round and make the relevant adjustment.

It's also led to us exploring (in the car) country lanes that we might have avoided for fear of getting lost - the "this *is* a road - trust me" effect. ;-)

The trick is to know when to ignore it, rather than following a satnav blindly as it takes me through an impassible ford. GPS is an aid, but it is not a substitute for keeping your eyes open and being aware of signs etc.

It was probably suffering from uninitialised variables in the phone software.

I have noticed that trees can block satnav location of "you are here" on my Garmin. That problem is a possibility in a rural setting.

Jim