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Transmission Park/Neutral Switch

DESCRIPTION
The park/neutral switch is located on the transmission housing and provides an input to the powertrain control module (PCM). This will indicate that the automatic transmission is in Park, Neutral or a drive gear selection.

OPERATION
This input is used to determine idle speed (varying with gear selection), fuel injector pulse width, ignition timing advance and vehicle speed control operation.

CIRCUIT OPERATION
Park/Neutral Position Switch
When closed, the case-grounded Park/Neutral position switch provides a ground path on circuit T41 for the coil side of the engine starter motor relay Circuit A41 from the ignition switch provides battery voltage to the coil side of the relay.

Circuit T41 splices to cavity A6 of the Powertrain Control Module (PCM). The Park/Neutral position switch provides an input to the PCM.