Permanent Program Functions

In addition to the manually-selectable gear-change programs (ECON, SPORT, WINTER), the Transmission Control Module (TCM) incorporates a number of preprogrammed functions which ensure that the correct gear is selected at all times based on the prevailing driving conditions. These functions vary by market and engine variant.

A When driving at high altitude, engine power is reduced due to lack of oxygen. The control module provides High Altitude Compensation by adjusting gear engagement times to suit the prevailing conditions, thereby maintaining high shifting quality.

B When the gear shift selector is in position D and the mode selector is set to ECON/SPORT, and the TCM registers throttle position and increases or decreases in road speed. The relationship between the throttle opening and speed change is registered as a measurement of the road gradient. The control module uses this information to select a gear. The function is known as "Up Slope Mode". "Up Slope Mode" is not available on cars with turbocharged engines.

C If transmission temperature increases abnormally as a result of heavy load in high temperatures, the torque converter lock-up function is activated as often as possible (temperature controlled lock-up). This reduces both slippage and the generation of heat in the transmission. If the temperature drops below +20°C the lock-up function will not be engaged. (This temperature can vary slightly depending on transmission type.) At low temperatures, the TCM increases transmission line pressure, shortening engagement times.

D/E The TCM is also programmed with certain safety functions which prevent manual engagement of gears which are too low if the speed is too high. Nor can reverse gear be engaged if speed exceeds approx. 5 km/h, even if the gear selector is moved to position R.