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Transmission Operation




The 41TE Transaxle features a fully adaptive control system. Adaptive control means that the transaxle adapts to changes that occur due to driver habit and transmission wear. Optimum shift scheduling is accomplished through continuous real-time sensor feedback information provided to the Transmission Control Module (TCM). This information includes, but is not limited to, the following:
- Throttle angle
- Vehicle speed
- Engine speed

Some information is used exclusively by the TCM to control transaxle operation, while others are shared (broadcast) over the CCD Bus to other vehicle computers. The input information provides the control system with information about overall driving conditions as it relates to shift selection and scheduling. Clutch Fill Volumes (CVIs) are constantly monitored and recorded in the TCM's RAM memory. In this way, as friction element wears, the TCM modifies the way it controls the output transaxle's devices (valve solenoids).

NOTE: Certain mechanical problems, such as broken return springs, can cause near zero (or incorrect) learned fill volumes. Incorrect fill volumes will result in setting the appropriate diagnostic trouble code. Internal transaxle failures are the most likely cause for these trouble codes.

Adaptive control is one feature of the 41TE that sets it apart from other transaxles. If the control system loses its ability to perform this function, then the problem must be identified and corrected by using the six-step troubleshooting procedure. By following proper procedures, effective repairs can be made to the transaxle.