Impreza 2.5 RS Sedan AWD F4-2.5L SOHC (2002)
While the vehicle is driving up a hill, the gear is fixed to the 3rd to avoid repeated gear shift between the 3rd and 4th gears.
When the vehicle is descending a steep slope at a speed of approximately 80 km/hour (50 miles/ hour), a 4th to 3rd downshift occurs automatically
when the brake pedal is depressed.
This gearshift control is cancelled when the accelerator pedal is depressed.
The TCM performs these controls based mainly on the throttle opening, engine speed and vehicle speed.
I: LEARNING CONTROL
The TCM has a learning control function with which it can adapt gear shift timing optimally to the current vehicle conditions by updating correction
factors in the memory.
For this reason, gear shift shock may become larger after the power supply is interrupted (disconnection of battery, flat battery, etc.) or immediately
after the ATF is replaced.
Larger gear shift shock after power supply interruption occurs because the correction data is reset to those for the new vehicle condition.
The TCM starts learning function again as soon as the power supply is restored. After driving for a while, therefore, the transmission will become able
to make gear shifts at the optimum timing. Larger shift shock immediately after ATF change is caused by change in friction characteristics of the
transmission internal parts. Also in this case, the transmission recovers shockless gear shifting after driving for a while.
J: REVERSE INHIBITION CONTROL
