A navigation system includes an operator interface module (OIM) including a display and keypad. A computer module (computer module) includes a CPU, map database and the motion and position sensors. A docking station is fixedly mounted in each of a plurality of vehicles. The docking station includes an electrical connector connected to the vehicle power supply and an electrical connector connected to a GPS antenna and an electrical connector connected to a display extension harness. The computer module and OIM are transportable among each of the vehicles. The computer module slides into the docking station and simultaneously makes electrical contact with the vehicle power supply, GPS antenna and display extension harness. The OIM is connected to the display extension harness, thereby connecting the OIM to the computer module. The OIM and computer module are thus transportable among multiple vehicles having the appropriate docking station.