1. A vehicle ignition interlock system, comprising: a breath analyzer located within a vehicle, wherein the breath analyzer comprises first and second alcohol sensors, each configured to detect breath alcohol levels of an operator of the vehicle, wherein the second alcohol sensor is a backup for the first alcohol sensor and becomes operational if the first alcohol sensor malfunctions; and a controller operably connected to the first and second alcohol sensors and to an ignition system of the vehicle, wherein the controller is configured to compare breath alcohol levels of the vehicle operator, as detected by either of the first or second alcohol sensor, with a threshold value, wherein the controller is configured to prevent vehicle ignition if a breath alcohol level detected by the breath analyzer is greater than or equal to the threshold value.