Door Ajar Warning Light Always On

The Office of Defects Investigation (ODI) opened this investigation on September 28, 2016 based on allegations that the "door ajar" light located on the instrument cluster stays on all of the time even when all doors are closed and fully latched on 2011-2013 model year Ford Edge vehicles. When the light is illuminated continuously, vehicle occupants cannot be certain if any of the doors are properly latched. Reported safety consequences as a result of this issue include doors opening while driving (because doors were initially not latched properly), doors cannot be locked while driving, and the interior dome lights staying on continuously. Ford data received from the Information Request letter corresponding to this investigation indicates the failures were caused by contamination of the electrical contacts on the switch located within each door latch that tells the vehicle if the door is open or closed. All four doors contain the same latch design and switch. According to Ford, the Body Control Module (BCM) monitors the position of the switch and continuously samples it to detect a state of change. After a closed door state is detected, a continuous wetting current designed to keep the electrical contacts clean is sent from the BCM to the switches as long as the BCM is active. Beginning with the 2011 model year Edge vehicles, a change in BCM strategy resulted in a reduction of the wetting current sent out to clean the switch contacts by more than 75%. Over time, this low level of current is not sufficient to keep the switch contacts clean and contamination build up causes them to fail as described above. During the course of this investigation, ODI has identified a total of 1,983 complaints related to the door ajar light. Of these complaints, 14 indicated that a door opened while driving. Twelve of the 14 door opening events were situations where an occupant of the vehicle (often a child) opened a passenger door because the doors were not locked. The remaining two c