TF-20
ALL-MODE 4WD SYSTEM
Revision: November 20092006 QX56
COMPONENTS FUNCTION
CAN CommunicationEDS002HC
SYSTEM DESCRIPTION
Refer to LAN-26, "CAN COMMUNICATION" .
Component parts Function
Transfer control unit Controls transfer control device and control valves.
Transfer control device Actuator motor and actuator position switch are integrated so as to switch driving types.
2-4WD shift solenoid valve Controls oil pressure and allows selection between 2WD and 4WD.
Clutch pressure solenoid valve Controls oil pressure and distributes torque (front and rear).
Line pressure switch Detects line pressure.
Clutch pressure switch Detects clutch pressure.
Transfer fluid temperature sen-
sor Detects transfer fluid temperature.
Wait detection switch Detects whether or not 4WD lock gear is locked.
Neutral-4LO switch Detects that transfer is under neutral-4LO condition (or shifting through neutral).
ATP switch Detects that transfer is under neutral condition.
4WD shift switch Allows selection from 2WD, AUTO, 4H or 4LO.
4WD warning lamp
Illuminates if malfunction is detected in electrical system of 4WD system.
There is 1 blink every 2 seconds if rotation difference of front wheels and rear wheels is large.
There is 2 blinks every 1 second if high transfer fluid temperature is detected.
ATP warning lamp Indicates that A/T parking mechanism does not operate when A/T selector lever is in
“P ” position
and transfer is under neutral condition.
4WD shift indicator lamp Displays driving condition selected by 4WD shift switch.
4LO indicator lamp Displays 4LO condition.
ABS actuator and electric unit
(control unit) Transmits vehicle speed signal via CAN communication to transfer control unit.
TCM Transmits the following signals via CAN communication to transfer control unit.
Output shaft revolution signal
A/T position indicator signal (PNP switch signal)
ECM Transmits the following signals via CAN communication to transfer control unit.
Engine speed signal
Accelerator pedal position signal
