Shift Pattern Selection Control
SHIFT PATTERN SELECTION CONTROLADAPTIVE CONTROL
This control is performed to improve the drivability of the vehicle by optimizing gear shifts in accordance with the drivers intention to accelerate or decelerate, and driving conditions such as hill climbing and descending, etc.
- Shift pattern automatic switching control
This control enables selection of the optimum gear speed by automatically switching the shift pattern by estimating driver's intentions and driving conditions through sensor information such as driving resistance, engine speed, acceleration, vehicle speed, and also from calculated values.
Any of the three patterns NORMAL, SPORTS, and SLOPE are continuously and automatically selected under the following conditions.
D range
NORMAL<=> SPORTS <=> SLOPE
D range, in sports mode
SPORTS <=> SLOPE
Normal pattern: covers a wide range from normal driving to high speed driving.
Sports pattern: a shift pattern suitable for driving conditions requiring deep accelerator pedal positions, such as winding road driving.
Slope pattern: this shift pattern controls upshifting to prevent too frequent gear shifting during climbing or descending hills. By combining braking control (in sports mode only) (explained later), engine braking will be positively used when descending hills.
- Accelerator pedal quick depressing control
When the accelerator pedal is quickly depressed, the TCM interprets this as acceleration is required, and the transmission is downshifted earlier to obtain a greater drive force.
- Accelerator pedal quick return control
When the accelerator pedal is quickly released, the TCM interprets this as deceleration is required, and upshift is prohibited in order to hold the transmission in the current gear speed to prevent frequent shifting and to maintain engine braking effect (operates in sports mode only).
- Braking control
According to the braking force (deceleration) during braking, downshifts are hastened to ensure engine braking effect and obtain a larger driving power for accelerating after braking (operates in sports mode only).
SPORTS MODE CONTROL
When the shift lever is moved toward the manual gate side in D range, the SPORT light in the combination meter illuminates and the system enters the Sports mode. Gearshift timings are set at higher vehicle and engine speeds to make more use of low speed gears. The full lockup vehicle speed in 4th is also set higher than in the normal mode.
MANUAL MODE CONTROL
By operating the "+" or "-" switch on the select lever in D range with the sports shift switch ON (in sports mode), the system switches to manual mode. In this state, operating the "+" switch causes upshifting while operating the "-" switch causes downshifting; manual shifting is enabled and the selected gear position is held while driving.
However, at certain vehicle speeds or ATF temperatures, the following inhibiting control is performed.
- Upshift inhibiting and auto downshift control
The gear upshifts each time the "+" switch is operated, however, when the vehicle speed is too low for the selected gear speed, the TCM inhibits further upshifting. If the vehicle speed becomes too slow for the current gear speed, a downshift will be made automatically to prevent engine stall. When the vehicle comes to a stop, the transmission will always be controlled to shift to 1st speed unless the vehicle was in Manual mode 2nd hold control.
- Downshift inhibiting control
The gear downshifts each time the "-" switch is operated, however, when the vehicle speed is too low for the selected gear speed, the TCM inhibits further shifting. A manual shifting inhibiting buzzer will sound to warn the driver.
- Engine over speed prevention control
If the engine speed exceeds the preset value during accelerating, the fuel supply is cut to prevent over-revving of the engine.
- Control when the temperature is low or hot
When the ATF temperature is low as in cases such as immediately after start in winter, upshifting to 4th is inhibited to quicken warm up. Upshifting to 4th is also inhibited if the ATF temperature becomes extremely high after severe driving, to prevent further temperature rise.
2nd HOLD CONTROL (IN MANUAL MODE)
When the "+" switch is operated when the vehicle is in Manual mode and not moving, the transmission shifts to 2nd speed enabling start in 2nd.This status is held unless the manual mode is canceled, or a speed other than 2nd is selected with the "-" switch. Also, the transmission is held in 2nd when the vehicle is stopped.
ILLUMINATION CONTROL OF VARIOUS INDICATORS
Illuminations of the various indicators on the combination meter are controlled in accordance with the shift pattern selection as shown in the figure.