When repairing a damaged/badly damaged CarDoor with Epoxy Putty or a Blowtorch, only the GlobalHealth of the Damagesystem will be affected, causing CarDoors (all Vanilla Cardoors btw) to not update their damage rvmat's, because those are defined in each Damagezone.
So the CarDoor will show Worn after a repair, but it will still show damaged or badly damaged, because the actual health of each Damagzone didn't change.

I tested this with all Vanilla CarDoors and modded ones with the same result.
After this, i tested it with several modded CarDoors which has no Windows and therefore no Damagezones and it worked as it should.

I think the issue is that ActionRepairCarPart sets Health after repair using GetMaxHealth which only returns GlobalHealth and not the Health of each Damagezone aswell.