Transmission Position Sensor/Switch: Description and Operation

PURPOSE
Prevents starting the vehicle except when gear selector is in "P" or "N" positions. Signals the powertrain control module engine (PCME) of gear shift position.

OPERATION
The powertrain control module transmission (PCMT) monitors the switch and relays gear select information to the PCME. The PCME uses gear position input from the inhibitor switch in its calculations for these outputs: fuel injection quantity, idle speed control, purge control, igniter (timing control), A/C cut-off.