1. A method for monitoring a transmission range selector connected to a transmission of a powertrain system, wherein the transmission range selector indicates one of a plurality of ranges including Park, Reverse, Neutral, and Drive, the method comprising: upon detecting a change in a target transmission range, monitoring, via a controller, whether a signal output from an on-board sensor indicates an achieved range position of the transmission, wherein detecting a change in a target transmission range includes detecting one of a change from Park to Reverse, Park to Neutral, Park to Drive, Reverse to Park, Reverse to Neutral, Reverse to Drive, Drive to Park, Drive to Reverse or Drive to Neutral; and when the signal output from the on-board sensor does not indicate that the target transmission range has been achieved: monitoring a transmission incorrect direction metric, monitoring a transmission unintended propulsion metric, and monitoring an elapsed time metric associated with achieving the target transmission range; and detecting a fault when any one of the transmission incorrect direction metric, the transmission unintended propulsion metric and the elapsed time metric is exceeded.