Communication dropout due to AT Command Seqeunce

I am using a pair of Xbee PRO S3B radios to communicate between two arduinos. I am having a strange intermittent dropout issue where the radios (every 5-15 minutes) stop communicating, causing an emergency stop to be triggered on the car (no valid packet received for 750ms). I am constantly sending packets using Arduino’s EasyTransfer library which uses raw binary structures to send packetized data between Arduinos. My question is, could this intermittent dropout be because the arduino happens to send a ‘+++’ in binary and the radio switches into AT mode? If not does anyone have any suggestions or settings to check?

Yes that would cause that. Try changing the command mode character on the radio to a - instead of a +. If that is the cause, your issue will then be solved.