The sliding door can be the subject of a variety of maintenance problems.
Door Card[]
The door card is secured by plastic clips that are adhesively bonded to the card. Over time this adhesive fails. Each clip has a base that attaches to the card and each one of these has an alphanumeric identifier embossed in it. This photo show the location of each clip base.
Each clip has a tab that is inserted through the slot, and movable when trying to install into the hole for panel to be held to the door.