I haven't seen your post regarding trailer lights. This is my own idea to interface OEM folding switch with cheap Chinese universal aftermarket mirror folding control module. Two extra relays allow for that and also there is no draw/load on the vehicle battery when ignition is off and mirrors are left folded in manually.
Also if you don't want to unfold on unlock you simply don't connect unlocking signal wire and mirrors unfold on ignition ON.

Wysłane z mojego SM-G973F przy użyciu Tapatalka