DTC P1899: P/N Switch Performance (A/T): Description

Park/Neutral Position (PNP) switch is referred to as Transmission Range Sensor (TRS). TRS operation is monitored when transmission is in Park, Neutral or Drive and not in limp-in mode. DTC will set in Powertrain Control Module (PCM) memory if PCM detects an incorrect transmission range sensor state for a given mode of vehicle operation. Possible causes for DTC to set are: defective transmission TRS, defective PCM, or defective connectors or wiring.