Transmission Adaptive Functions: General

The changing duration is calculated in real time by comparing the speeds of the input shaft and output shaft. The control module knows the gear ratio for the current gear and the target gear and can follow the change in gear ratio until the changing process is complete. The time it took to change gear is then compared with the desired value for the gear change and an adaptation is made.

The adaptation is done by correcting the requested pressure for the applied friction element solenoid and the correction is then used the next time a change is made between these gears. The adaptation value is saved in a non-volatile memory and must be zeroed using a scan tool each time the TCM, transmission or valve housing is changed and after SPS programming.

After zeroing with a scan tool, it will usually only require a road test, see below, for the TCM to be able to adapt itself to the new conditions.