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Transmission Position Sensor/Switch: Description and Operation

PURPOSE
The Park/Neutral Position (PNP) switch indicates to the Powertrain Control Module (PCM) when the transmission is in park or neutral verses another range (one of the drive ranges or reverse).

This information is used for the Torque Converter Clutch (TCC) and Idle Air Control (IAC) valve operation.

NOTE: Vehicle should not be driven with PNP switch disconnected, as idle quality will be affected and a possible false Diagnostic Trouble Code (DTC) 24 (Vehicle Speed Sensor) may set.