Rover 75 Saloon, Owner'S Handbook Manual

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Automatic Transmission
AUTOMATICALLY SELECTED MODES
NOTE: Automatically selected modes cannot be selected by the driver and
will not operate if Sport or Snow mode are selected.
The transmission control system automatically selects different gear
change modes, listed below, designed to suit a variety of driving
conditions.
•
Hill ascent, trailer and high altitude mode
A suitable gear change pattern is selected to counter
momentum loss, caused by the more frequent gear changing
which can occur when climbing hills, or when towing a trailer
or caravan. This gear change pattern is also selected at high
altitudes to combat low engine torque.
•
Hill descent mode
Unless some form of braking is applied, vehicles will naturally
increase speed when travelling down hill. On most automatic
vehicles, this results in the highest gear being selected, thereby
reducing engine braking to a minimum.
On this car however, the hill descent mode applies a brake
within the transmission and, depending on circumstances,
changes to a lower gear, or (more commonly on diesel engine
cars) inhibits automatic selection of higher gears.
Hill descent mode will only be activated when the accelerator
pedal is fully released, and when some braking effort has been
applied but a certain amount of acceleration is still occurring.
The precise operating parameters of hill decent mode will differ
according to engine type.
NOTE: Hill descent mode is not designed to be driver-activated, or to
replace the good practice of selecting an appropriate low gear for steep
descents, or making normal use of the brakes at all times.
•
Cruise control mode
When cruise control (if fitted) is activated, a suitable gear
change pattern is selected which is less sensitive to throttle
changes. This reduces the amount and frequency of gear
changes, providing a smoother ride.
•
Cold start mode
In very cold conditions the automatic transmission will stay in
the lower gears for longer, to help the engine reach its normal
operating temperature more quickly. This will help to improve
overall fuel economy and driveability, and reduce emissions.
•
High coolant temperature mode
In high ambient temperatures during extreme load conditions,
it is possible for the engine and the gearbox to overheat. At a
certain temperature, the transmission will select a gear change
pattern designed to aid the cooling process, whilst enabling the
gearbox to continue performing normally in high temperatures.
•
Smooth change mode
Engine torque is reduced during gear changes, creating a much
smoother ride.