2012 won't start
 

I have a 2012 that sometimes won't start and my dealership can't figure it out.. seems to be when it is cold in the morning. When you turn the key, the anti theft flashes rapidly, it cranks about 3 times and quits. After that, when you turn the key, the anti theft flashes and nothing happens. It doesn't happen every time it's cold, but every time it does happen, it is cold out.. If I can get it to eventually start, it starts fine for the rest of the day. HELP, PLEASE.

Please if you can,
When you say it cranks about3 times and quits does that mean it tries to start and then stops trying to turn the engine over any more , just clicks, or does absolutely nothing when you attempt to start it?
The blinking anti-theft lite is attempting to tell us something.
If your vehicle uses a FOB, when was the battery last changed?
If you have another FOB or key , what does it do with the second FOB or key?

It tries to turn over and then quits. After that, it does nothing when you turn the key. New battery in the car and new batteries in the key and the spare key. My mechanic says it shows a network error when the run diagnostics, but they can't figure out what that means, apparently. Took both keys in and they reset the system. No change. They also cleaned all connections and changed a relay.

A wiring diagram will be required to determine what is sharing the network with the security system and then checking the modules on that system for opens or shorts. A good scan tool will be required to accomplish this.
It helps to know what model vehicle you have since they don't all use the same system.
The dealership should have all the necessary equip to troubleshoot this problem. It does sound like it is a poor connection in the system that once the vehicle warms up the problem is temporarily gone. It might require that you leave the vehicle for a few days when it is cold and it can be checked on site where it is parked.

They have had it off and on for a month and a half... just hoping someone has had this issue before and found the solution.

I can sympathatise with your situation, but there are so many possible reasons for something like this , which could even be something like a cold solder joint anywhere in the system. Something like this is a tech's nightmare because intermittent problems can take so long to pin down. There have been times when the cause of a problem just refused to be found and the "shotgun approach" was the only practical solution and the old parts were reinstalled one at a time to attempt to pin down the questionable part.And even then the darn part would work until it decided to quit working. So ,hope you can get some idea of how frustrating this can be for everybody.