Toyota Tundra 2005 Service - Repair - Maintenance page 4120

System Outline
In the conventional system, the 2-4 select SW and the transfer shift lever was used to shift the mode between H-L. In this
system, the transfer shift lever is not used, and the H-L mode shift can be done by the transfer shift actuator.
The mode can be changed by the touch select 2-4 SW and touch select high-low in the integration control and panel.
The shift range is controlled according to the vehicle speed sensor and Park/Neutral position SW, and the indicator light is
turned ON to inform the driver if any of the following conditions are detected:
∗ The shift is not completed even though 3 seconds have elapsed after transfer operation.
∗ The vehicle speed is above approximately 100 km/h (63 mph) when shifting from H2 to H4.
∗ The vehicle speed is below approximately 5 km/h (3 mph) or the A/T shift lever is in a position other than N position, when
shifting from H4 to L4 or visa versa, and from L4 to H2.
Transfer Operation
H2 to H4
When the touch select 2-4 SW in the integration control and panel is turned ON, a signal is input into TERMINAL (A) 8 of the
4WD control ECU.
The 4WD control ECU is activated by this, and the current flows from the 4WD control ECU TERMINAL (B) 2 to transfer shift
actuator TERMINAL 2 to motor to TERMINAL 1 to 4WD control ECU TERMINAL (B) 1 to GROUND, and the transfer shifts to
4WD (H4 position.)
When the system shifts to 4WD, the detection SW (Transfer 4WD position) is turned ON, and the current flows from 4WD
control ECU TERMINAL (A) 2 to ADD actuator TERMINAL 5 to motor to TERMINAL 1 to 4WD control ECU TERMINAL (A) 1
to GROUND, and the ADD actuator is activated, and the ADD is connected. When the ADD is connected, the detection SW
(ADD position SW) is turned ON, and the 4HI Indicator light comes ON.
H4 to H2
When the touch select 2-4 SW in the integration control and panel is turned OFF, a signal is input into TERMINAL (A) 8 of
the 4WD control ECU.
The 4WD control ECU is activated by this, and the current flows from the 4WD control ECU TERMINAL (B) 1 to transfer shift
actuator TERMINAL 1 to motor to TERMINAL 2 to 4WD control ECU TERMINAL (B) 2 to GROUND, and the transfer shifts to
2WD (H2 position.)
When the system shifts to 2WD, the detection SW (Transfer 4WD position) is turned OFF, and the current flows from 4WD
control ECU TERMINAL (A) 1 to ADD actuator TERMINAL 1 to motor to TERMINAL 5 to 4WD control ECU TERMINAL (A) 2
to GROUND, and the ADD actuator is activated, and the ADD is disconnected. When the ADD is disconnected, the
detection SW (ADD position SW) is turned OFF, and the 4HI indicator Light turns OFF.
H4 to L4
When the touch select high-low SW in the integration control and panel is turned ON, a signal is input into TERMINAL (A) 15
of the 4WD control ECU.
The 4WD control ECU is activated by this, and the current flows from the 4WD control ECU TERMINAL (B) 2 to transfer shift
actuator TERMINAL 2 to motor to TERMINAL 1 to 4WD control ECU TERMINAL (B) 1 to GROUND, and the transfer shifts to
4WD LO position (L4 position.)
The 4HI Indicator is turned OFF and the 4LO indicator is turned ON.
L4 to H4
When the touch select high-low SW in the integration control and panel is turned OFF, a signal is input into TERMINAL (A)
15 of the 4WD control ECU.
The 4WD control ECU is activated by this, and the current flows from the 4WD control ECU TERMINAL (B) 1 to transfer shift
actuator TERMINAL 1 to motor to TERMINAL 2 to 4WD control ECU TERMINAL (B) 2 to GROUND, and the transfer shifts to
4WD HI position (H4 Position.)
The 4HI indicator is turned ON and the 4LO indicator is turned OFF.
The shift is not completed even though 3 seconds have elapsed after transfer operation.
∗ The vehicle speed is above approximately 100 km/h (63 mph) when shifting from H2 to H4.
∗ The vehicle speed is below approximately 5 km/h (3 mph) or the A/T Shift Lever is in a position other than N position,
when shifting from H4 to L4 or visa versa, and from L4 to H2.
L4 to H2
When the touch select 2-4 SW in the integration control and panel is turned OFF, a signal is input into TERMINAL (A) 8 of
the 4WD control ECU.
The 4WD control ECU is activated by this, and the current flows from the 4WD control ECU TERMINAL (B) 1 to transfer shift
actuator TERMINAL 1 to motor to TERMINAL 2 to 4WD control ECU TERMINAL (B) 2 to GROUND, and the detection SW
(Transfer L4 position) is turned OFF.
Furthermore, the motor rotates to shift the transfer to 2WD (H2 position.)
When the system shifts to 2WD, the detection SW (Transfer 4WD position) is turned OFF, and the current flows from 4WD
control ECU TERMINAL (A) 1 to ADD actuator TERMINAL 1 to motor to TERMINAL 5 to 4WD control ECU TERMINAL (A) 2
to GROUND, and the ADD actuator is activated, and the ADD is disconnected. When the ADD is disconnected, the
detection SW (ADD position SW) is turned OFF, and the 4LO indicator light turns OFF.
2005 TOYOTA TUNDRA (EWD611U)
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