Just because you replaced a sensor, doesn't mean the sensor plug or sensor wires are good.
More details are required:
When your Jeep won’t start :
1) Do all the gauges display correctly when it is not starting, or does the fuel gauge and/or voltage gauge not work at all, or not display properly ?
2) Does the fuel pump prime and run for 3-5 seconds when you turn on the key ?
3) Have you tried wiggling the automatic transmission shift lever when trying to start, in both PARK and NEUTRAL ?
4) When you turn the key does nothing happen, and you hear no sounds ?
5) Does the starter not engage, and you only hear a clicking sound from under the hood ?
6) Does the starter engage, make the starter sound, and cause the engine to turn ?
7) Does the engine sputter and try to run, or does it not start or run at all ?
8) If you depress the gas pedal about halfway during starting, does the engine start up and run ?
Answer yes/no to all by the numbers.
Have your helper turn the key to start the engine while you gently tap on the starter with a hammer. If the engine starts, you need a new starter. If wiggling the automatic transmission shifter starts the engine, you need to clean or replace the Neutral Safety Switch (NSS).
Get your Volts/Ohms multimeter. With the key in the ON position, check for voltage directly at the starter. If you have approximately 12.0 volts or more battery voltage at the starter, the problem is may be the starter. If you have no voltage at the starter, the NSS and the ignition switch are suspect and need to be inspected/tested. If you test less than 12.0 volts at the battery with the engine off, the battery is weak and needs to be charged or possibly replaced. The starter, alternator, and battery can all be load tested at the auto parts store.