The present disclosure provides systems for microprocessors to control a transmission power relay output with a latchdown mechanism in the event that either microprocessor decides it is appropriate to de-energize the relay. Advantageously, the present disclosure allows, for example, the transmission control to be performed by an existing dual microprocessor configuration instead of a custom-designed application specific integrated circuit (ASIC). The microprocessor-based software is more easily updated or changed to add functionality. Further, the present disclosure minimizes unique development with respect to electronic transmission control with a less complex design.