On top of the dash near the windshield.
According to the owner's manual - headlight bulb # 9007
where the ford symbol is
According to the 2003 Ford Explorer Sport Trac Owner Guide : ( # 9007 bulb is used in the headlights )
Its part of the MAF sensor. In 98 they integrated it.
On your 1998 Ford Explorer Sport : The mass air flow sensor is between your engine air filter and the big rubber engine air intake tube
Intake air Temp sensor, should screw into the side of your air cleaner housing.
Bank 2 is the drivers side of the engine in your Ford Explorer Sensor 2 is after the catalytic converter ( downstream )
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To replace the headlight on a 2007 Ford Explorer Sport Trac, start by opening the hood and locating the headlight assembly. Remove the plastic cover or bolts securing the assembly, then disconnect the wiring harness from the back of the headlight. Carefully twist and pull out the old bulb, and insert the new bulb without touching the glass. Reconnect the wiring harness, secure the headlight assembly back in place, and close the hood.
Bank 1 is the passenger side of the engine in a Ford Explorer Sensor 2 is in the exhaust after the catalytic converter ( downstream )
The sensor is located under the oval shaped panel on top of your dashboard. Should pull right up and you will see the sensor attached to the bottom of this panel.
Could be that the sensor in the door isn't registering that the door is closed.