DTC P1899: Park/Neutral Switch Stuck In Park Or Gear: Description

Circuit is monitored when transaxle is in Park, Neutral or Drive and not in limp-in mode. DTC will set if PCM detects an incorrect Park/Neutral Position (PNP) switch state for a given mode of vehicle operation. Possible causes are: defective Transmission Range Sensor (TRS), TRS T41 sense circuit open or shorted to ground, or defective PCM.