Upshift Telltale

On manual transaxle vehicles, the ECM optimizes fuel economy by informing the driver when the transaxle should be shifted to the next higher gear. The ECM bases its determination on engine speed, vehicle speed and engine load. When the ECM determines that the driver should shift to the next higher gear, it sends a message via the CAN bus to the BCM. The BCM sends a message over the Class II link to turn On the Upshift telltale.