DTC P0723: Countershaft Speed Sensor Intermittent Failure: General Description

The countershaft speed sensor is attached to the outside of the transmission housing. The countershaft speed sensor generates a pulsing signal according to the speed of the park gear on the countershaft. Using that signal, the powertrain control module (PCM) determines the speed of the countershaft. If pulse dropouts occur with the countershaft rotating, the PCM detects a malfunction that may be caused by an open, a temporary open, or a short to ground. Based on the fluctuation of the vehicle speed measured by the countershaft speed sensor, a malfunction is detected and a DTC is stored.