J2000/Sunbird V6-191 3.1L VIN T MFI (1994)
Shift Indicator: Description and Operation
Gage Cluster
In the LA VIN H and V6 VIN T with Manual Transaxle, a bulb lights when the car should be shifted to the next higher gear for better fuel economy.
Battery voltage is applied to one side of the bulb. The other side of the bulb is switched to ground by the Engine Control Module (ECM) which uses
engine data such as rpm, vehicle speed, and intake vacuum to compute an efficient shift point.
