Do you plan to issue an 0.17 update for this mod?

It never got any updates... but I can tell you how to fix it.

Go to your mods folder for the game
Open (don't extract) Gizmos_Car_Keys_0.16.0.zip
Open Info.json
Change "factorio_version": "0.16", and "dependencies": ["base >= 0.16.0"] to 0.17.
Save and close
Open the folder "Prototypes"
Open item.lua
Delete the line flags = {"goes-to-quickbar"}, and I mean don't leave an empty line there
Save and close
Save changes made to the archive
Start game

Works for me at least. However I have not the faintest clue about coding (I just figured setting the base game dependency was needed and then realized that the "goes-to-quickbar" flag must have been removed when the quickbar became a set of hotkeys) so no idea if this won't delete your game or brick your PC in the long run.
Basically, use at own risk.

Actually I just changed a few minor things along with the fix and reuploaded it.
https://mods.factorio.com/mod/Gizmos_Car_Keys_Z_Patch

Zahnfeechen, thank you very much!!!

Have you seen my mod yet? It updates this one to 0.17, it fixes that grid equipment is lost on summoning vehicles and that a vehicle owned by one player can be claimed by another one. The next version will include further improvements, the most important being that locked vehicles without an owner can only be claimed by the player who locked them (already works) and that you can teleport the vehicle between surfaces (still working on that).