I had a similar problem with my mother in law's ([:@])Toyota Camary. The solenoid was making the same clicking sounds as your explorer and the lights weren't dimming very much. Tried to jump it to no avail and finally checked the battery. There was so much corrosion that I had to use a cold punch to spread the ears on the connector. Got everything as clean as possible and re-connected the cables...she started up without even needing a jump.

 

I don't think it is the battery. I tried to jump it off with my truck and nothing. I check the connections at the battery and they look fine. Put a new battery in about 2 yrs ago.

 

I would also go with the starter....My father in law had the same thing happen to him and it was the connection between the solenoid and the starter. just take those apart and clean them up and try again.

Brad

 

Ok, definitely not the battery. Cleaned it uyp last night. I had my wife turn the key and I listened under the hood for the clicking sound. Seems to be coming from the bottom drivers side. I am leaning toward the starter or the connections.

 

anyone know where i can find an online diagram of the 4.0 ford motor?

 

Maybe you could find your answers here...

http://www.explorerforum.com/forums/...rune=&f=92