Abstract: A device and method for activating the electronic odometer of a vehicle without using an electrical power source residing on the vehicle. The device is housed in a portable case and includes an electrical power source, a load circuit for connecting the power source to the electrical system of a vehicle, and a fault protection circuit that is electrically in parallel with the load circuit for protecting the vehicle and the device from damage that could otherwise result from a short circuit in the vehicle's electrical system. The method includes a series of steps that involve connecting electrical power to the vehicle's computer and various electrical subsystems in a predefined order.