I replace the cover of my arm rest and remounted the arm rest by bolting in the screw.
Seems easy, but now the arm rests falls downward instead of staying horizontal (in different positions).
How can I solve this? Any suggestions?
Yes. The armrest is internally "keyed" to stop at the "bottom" spot and work normally. You need to remove the bolt and reorient the whole armrest by rotating it (including the base, not just the swivel part) until the "bottom" position returns to normal, then reattach the bolt.