There are a variety of different reasons for having to reset the computer on a Ford Explorer. For example, when you add new equipment or replace engine components, you will need to reset the computer so it recognizes the new parts. Another reason is a check engine light staying on while you are driving. This is a sign that something is wrong with the engine in your Ford Explorer. Resetting the onboard computer will usually turn the light off temporarily.
Open the hood: release the primary latch by pulling the release lever under the steering wheel near the floor board.