Why is my 2002 Ford Explorer door ajar flashing?

The "door ajar" warning light on your 2002 Ford Explorer may be flashing due to a malfunctioning door switch, which detects whether the door is fully closed. It could also indicate that one of the doors or the rear hatch is not fully closed or that there is a wiring issue. Additionally, dirt or debris in the door latch mechanism can cause the sensor to malfunction. Checking each door and the rear hatch for proper closure and inspecting the door switches can help resolve the issue.