A very odd glitch - A bizarre route deviation in the Navigation app

[Richard 18]

I drove today from Cap Gris Nez (near Calais) to Arnage, near Le Mans.

To drive the route I created it in MyRoute first. As it’s a fairly simple motorway only A to B drive, I simply shaped it a little to pass to the west of Le Mans before coming back again to enter Arnage. I then used the expand function to place a waypoint roughly evey 3 miles / 5 km as recommended.So far, so good.

I am conscious that using the expand function can sometimes place a point away from the road, so I carefully checked each one, moving any that looked badly placed. I was then happy that everything was correct.

I then exported the route in version 1.1 to my Garmin XT where it imported and ran perfectly.

I also imported the route in 1.1 into my iPhone to run in parallel using the MyRoute Navigation app. This is where something odd happened.

A. In the route created in MyRoute, the route between points 14 and 15 simply follows the motorway.

B. On my XT, this is exactly what it did; no problem at all.

C. In the MyRoute Navigation app, the route displayed develops a really strange detour between points 14 and 15, which I really cannot understand.

Here is the route:

https://www.myrouteapp.com/en/social/route/9188471?mode=share

Here is a screen shot of points 14 and 15 showing MyRoute displaying the route perfectly:

Here is a screenshot, taken on my iPhone as I drove along. It shows the bizarre, app created, loop.

I must stress that:

A. Other than this very curious glitch, the Navigation app and route ran perfectly.

B. My XT did not show the same bizarre glitch. It, quite correctly, routed me from point 14 to 15 and then (correctly) told me to leave the motorway at exit / junction 23. MyRoute app told me to exit at 24 and make the very strange loop.

Any ideas why this happened?

Thank you.

Richard

PS

iPhone 15 ProMax running iOS 17.4.1

MyRoute Navigation app version 4.1.3 running in off-line mode

All maps freshly installed and up to date

Route created in HERE maps in motorhome mode.

PPS I have just checked it again this evening and the glitch is repeating itself.

[Nick Carthew]

@Richard-18 The advice for positioning route points has always been; avoid placing too close to roundabouts, junctions and viaducts. Route point 15 is on a viaduct.

[Richard 18]

I think I have just worked out why….

Point 15 was generated by the expand function.

It is on the correct carriageway of the motorway but appears to be on a bridge (or something like that) where the motorway runs over or under a very
minor provincial French road. I didn’t spot it when I made my check!

I guess the Navigation app read point 15 as being, not on the motorway but on the minor road?

This would at least explain the bizarre loop the Navigation app displayed. Troubling though (or very good) that MyRoute and my Garmin XT did not read it that way, too.

Richard

[Richard 18]

Thank you, Nick.

I spotted it just as you replied.

I missed point 15 when checking the other 73 points, several of which I had moved for exactly the reason you gave.

All is well now.

Richard