Theory Of Operation
WARNING: This page is about a different car, the 2017 Jeep Patriot and 2017 Jeep Compass. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of this diagnostic is to check the electrical and rationality performance of the transmission range sensor (TRS) circuit. The range sensor circuit is connected to the TCM by four independent circuits which distinguish between the possible shifter positions (park, reverse, neutral, and drive). The shifter position is determined based upon a 4-bit pattern (S1, S2, S3, and S4).