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Shift Patterns

Shift Patterns

Upshifts

Upshifting is controlled by the powertrain control module (PCM). The PCM receives inputs from various engine or vehicle sensors and driver demands to control shift scheduling, shift feel and torque converter clutch (TCC) operation.

The PCM has an adaptive learn strategy to electronically control the transaxle which will automatically adjust the shift feel. The first few hundred miles of operation of the transaxle may have abrupt shifting. This is a normal operation. If the battery has been disconnected for any reason it will need to be kept disconnected for approximately 20 minutes to reset the adaptive shift pressure strategy or use the diagnostic tool to clear the transmission keep alive memory (KAM) tables.

Downshifts
Under certain conditions the transaxle will downshift automatically to a lower gear range (without moving the transaxle range selector lever). There are three categories of automatic downshifts: coastdown, torque demand, and forced or kickdown shifts.

Coastdown
The coastdown downshift occurs when the vehicle is coasting down to a stop.

Torque Demand
The torque demand downshift occurs (automatically) during part throttle acceleration when the demand for torque is greater than the engine can provide at that gear ratio. If applied, the transmission will disengage the TCC to provide added acceleration.

Kickdown
For maximum acceleration, the driver can force a downshift by pressing the accelerator pedal to the floor. A forced downshift into a lower gear is Possible below calibrated speeds. Specifications for downshift speeds are subject to variations due to tire size, engine and transaxle calibration requirements.