I have a 99 F-150 (5.4L...4x4 auto trans) that wont start. I tested the starter and it turns. If I connect it directly to the battery it will even start but when i jump in the cab and turn the key...NOTHING. All lights come on and no warnings. I've elminated everything but the STARTER RELY and the TRANSMISSION RANGE SENSOR. How do I test both of these?

My ideas so far...I think as long as I disconnect the Tran. Range Sensor from the starter reply and it still doesnt start then its my reply...but if it does its my Trn Range Sens. Do my logic completely elminate one or the other??