ELECTRONIC CONTROL SYSTEM



  • The clutches and brakes have dedicated solenoid valves. This enables each clutch and brake to be controlled independently and directly with a system of "clutch-to-clutch" control.
  • The incorporation of feedback control and a learning function into the gear shifting process, combined with integrated control of the engine and A/T, realizes a superior shift feeling during all gear changes.

SYSTEM CONFIGURATION DIAGRAM




SENSORS AND ACTUATORS


Item
 Function
Sensor
 Input shaft speed sensor
 Detects when input shaft speed
Output shaft speed sensor
 Detects when output shaft speed
A/T fluid temperature sensor
 Detects A/T fluid temperature
Inhibitor switch
 Detects selector lever position
Overdrive switch
Detects whether overdrive is on or off (D range-4th gear)
4LLc operation detection switch
 Detects transfer is 4LLc position
Actuator
 A/T control relay
Turns solenoid valve power supply circuit ON/OFF
DCC solenoid valve
 Regulates hydraulic pressure to damper clutch control valve
LR solenoid valve
 Regulates hydraulic pressure to pressure control valve (for gear shift control)
2ND solenoid valve
UD solenoid valve
OD solenoid valve
Selector lever position indicator lamp
 Indicates that fail-safe is active
A/T fluid temperature warning lamp
 If A/T fluid temperature increases excessively, A/T fluid temperature warning lamp lights up to inform.

INPUT SHAFT SPEED SENSOR/OUTPUT SHAFT SPEED SENSOR



  • The sensors utilize Hall elements.
  • The input shaft speed sensor and output shaft speed sensor differ externally but are constructed in basically the same manner.
  • The input shaft speed sensor detects the turbine speed at the REV clutch retainer.
  • The output shaft speed sensor detects the output shaft assembly.
  • With a current flowing in the Hall element, the application of a magnetic field at 905 to the current creates a voltage perpendicular to both. This voltage is proportional to the current and magnetic field strength. This phenomenon is known as the Hall effect and is utilized by the input and output shaft speed sensors. The input shaft speed sensor detects the voltage that is created by changes in the magnetic flux density around the sensor’s internal magnet. Changes in the flux density are caused by rotation of the REV clutch retainer. The output shaft speed sensor functions in the same manner, detecting the voltage that is created, via the process described above, by rotation of the output shaft assembly.

A/T FLUID TEMPERATURE SENSOR


  • The A/T fluid temperature sensor and its connector are combined into a single unit.
  • The thermistor characteristics are the same as those of earlier A/T fluid temperature sensors.

INHIBITOR SWITCH
The inhibitor switch is a 7-position type.

SOLENOID VALVES


  • The DCC, LR, 2ND, UD, and OD solenoid valves are all of the same type.
  • The solenoid valves are a normal-open type whereby the passage between the supply and output ports is open when no current is flowing.

4LLC OPERATION DETECTION SWITCH

A contact-point switch mounted in the transfer detects a transfer in the 4LLc position.