An electronic air charge controller for a tractor trailer vehicle air brake system includes a micro controller, a first pressure sensor interface coupled to the micro controller, a second pressure sensor interface coupled to the micro controller, and a vehicle control protocol interface coupled to the micro controller. The micro controller, in response to a signal received from the first pressure sensor interface indicative of an air supply recharge condition, a signal received from the second pressure sensor indicative of parking brake engagement condition, and a signal from the vehicle control protocol interface indicative of an engine start condition, supplies a maximum engine speed control signal to the vehicle control protocol interface. The time required to charge the air supply system to the required normal operating level is thereby minimized. In addition, a transmission sensor interface is preferably coupled to the micro controller. The micro controller does not generate the maximum engine speed control signal unless a signal supplied by the transmission sensor interface indicates that an automatic transmission is in park or a manual transmission is in neutral. Still further, to improve operating efficiency, a vehicle load condition signal is supplied by the vehicle control protocol interface to the micro controller. In response, the micro controller supplies a pause air compressor charging cycle signal or a pause air dryer recycle signal to the vehicle control protocol interface, if either the air compressor or air dryer is operating when a high load condition is encountered.