Transmission Position Sensor/Switch: Description and Operation
Transmission Range Switch:
PURPOSE
The Transmission Range (TR) switch serves a dual purpose:
- Prevents unintentional vehicle movement caused by engine cranking and starting with the shift control selector lever in a forward or reverse position.
- Informs the Powertrain Control Module (PCM) that the transmission is either in neutral or any other gear. Input is used in PCM calculations for fuel injection quantity, idle speed, A/C cut-off, and purge control.
OPERATION
Manually controlled by the shift control lever and transmission shift cable. When the transmission is in PARK or NEUTRAL, switch is ON (shows continuity).