[sanghill]

Is the odometer flashing with the ignition in RUN?
Is the Check Engine light flashing?
If the Check Engine light is ON try to get the codes.
Any indication rodents have been chewing on the wiring in the engine compartment?
Check the fuses and relays in the PDC under the engine hood.
Refer to this Post: Check those fuses and relays!
Probably you have the V6 engine?
Corroded ground cables can be a problem.
Do you go off road, cross rivers, or drive in lots of salt?
Make sure the battery cable clamps are on tight, make sure you can not twist and move them.
Do have an aftermarket alarm system?
Search for "won't start" in Search Community above, there are several Posts on this Forum that may help.

 

[sanghill]

Get the "battery health" checked and/or load tested.
Don't know if diesels still have glow plugs but they draw a lot of current. Enough to cause a weak battery to fail.
Does the starter get the engine to "turn over" or does the starter solenoid just click?
Check the battery voltage with a voltmeter or put the ignition in RUN and check the battery voltage on the EVIC screen.
12 volts or less and the battery needs to be charged and the battery may still have failed.
Use a battery charger with an AGM selection and charge at the 10 amp rate.
Find out what check engine error codes you have. There will be a lot of them.
The chances of all those different systems failing is slim to none.
Then the challenge is figuring out which was the first and most important error code.
Blinking odometer means a Jeep dealer needs to do a Proxy Alignment, after the real problem is corrected.
Get flat bed towed to a Jeep dealer, preferably the one you bought the Jeep from.