A multi-combination vehicle having at least two engines, each engine having a transmission coupled thereto, each transmission including an electronic control unit, each engine including an electrical power source adapted to provide power to a respective one of the electronic control units. The multi-combination vehicle further including an electronic gear selector in communication with each transmission, the gear selector having a power input and a gear selector output, and a gear selector module that is provided power from the electronic control units, the gear selector module including a manual switching device that is adapted to selectively provide the electronic control unit power.