Started a short local ride following a loaded course to see what had "improved" in 17.29 and as almost always I had Turn Guidance Disabled (OFF).
First surprise, no chevrons on the map and second surprise the navigation instructions at the top of the map had no relationship to the course I was following.
The instructions on top of the map were a double surprise as I had "Guide Text" set to "When Navigating" ie only if Turn Guidance was ON. The top of map and "Turn List" instructions were both for a much longer (200kms) course I had done 6 months ago which started about 25kms from my real starting point. The "Course Points for my real (loaded,11.37 km) course were listed in the Course Point List. As I progressed in the ride the Ghost Course instructions on the map advanced as did the WPT NEXT data field.
And the most surprising is that after this sort of thing happened to me before I had kept my courses on the device to a minimum and this course was not in the Courses directory or the Cals or PointCache directories. WHERE was the 1040 getting these instructions from ??? When I finished I scanned the 1040 file directories but could not find any trace of the Ghost Course.
aweatherall has said there is a "ticket" raised regarding this so I hope Garmin developers are working hard on a solution as it is becoming a BIG PAIN.
To help them along I have done a quick scan of the forums here for threads posted by users regarding these problems, I came up with 12 (plus 4 more since) in the 1040 forum over the last 12 months and various software versions from the original released version up to the current 17.29 and 2 in 840 forum (it's only new) , the first one contains a summary of the observed issues on page 6, Garmin, let me know if I can assist more.
A summary of the major aspects of this issue are
People see some of a number of issues including,
- Most frequently no chevrons on the course they are following (because the chevrons are on the ghost route)
- Getting "turn Guidance" (instructions and big white arrows) not related to the course they have loaded (happens both if Turn Guidance is enabled or disabled)
- An actual ghost course in the pink route color as well as a separate (completely different) magenta loaded course
- Various off course & re-route prompts even though the position cursor is on the loaded route (Virtual Partner is too)
- Can get both Course Point notifications on a loaded course AND Turn Guidance notifications from a different ghost course especially if TG is OFF.
- Often the issue is triggered by some GPS issue/ lost signal such as a tunnel or other temporary interruption
1040 Series
https://forums.garmin.com/sports-fitness/cycling/f/edge-1040-series/331170/odd-navigation-behavior
forums.garmin.com/.../another-ghost-course-wrong-navigation-instructions-17-29 (this thread)
https://forums.garmin.com/beta-program/edge-1040-series/public-beta-bug-reports/i/edge-1040-series---18-xx-bug-reports/new-beta---old-ghost-rides (still in beta 18.15)
840 Series
https://forums.garmin.com/sports-fitness/cycling/f/edge-840-series/332859/turn-by-turn-directions
https://forums.garmin.com/sports-fitness/cycling/f/edge-840-series/336218/chevron-gone