What's the 2004 Ford Explorer starter solenoid location?

On the 2004 Ford Explorer, the starter solenoid is located on the starter itself; it's integrated into the starter motor, so You'll need to replace the entire apparatus if replacement is Your end goal. However, it should be noted that a failure of the solenoid is not a very common occurrence; if You have issues with the starter that You feel can be traced back to electrical causes, the starter relay is a better place to start. Of course, relays are much less expensive than starters, so it's a good first diagnostic step to try. The starter relay is located in the engine compartment within the relay panel. It's the black, middle relay located on the second to top row of the box.