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Home >> Saturn >> 2003 >> ION L4-2.2L VIN F >> Repair and Diagnosis >> Transmission and Drivetrain >> Continuously Variable Transmission/Transaxle >> Description and Operation >> Transmission Adaptive Functions
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Transmission Adaptive Functions


Transmission Adaptive Functions
The Hydra-Matic VT25-E uses a line pressure control system which has the ability to adapt the system line pressure in order to compensate for normal wear of clutch fiber plates, seals, springs, etc. The adapt feature is similar in function to fuel control (integrator/block learn).
The Hydra-Matic VT25-E transmission uses the adapt function for garage shifts, ratio control, and TCC application. The TCM monitors the input shaft speed in order to determine if the ratio control is occurring too fast or too slow and adjusts the pressure control solenoid in order to maintain the proper ratio control and garage shift feel.
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