96 Stratus stalling problems

Just bought a used 96 Stratus, and the engine has stalled a few times while driving on the highway. No worning, just shut off. Lights stayed on, so was not the battery. Pulled over, and car would not start. 5 minutes later it started. This has happened a couple of times. There was also a message showing on the odometer when trying to start "NO BUS". Dealership did not find anything wrong after hooking up the the computer. Need help. Any suggestions?