Toyota Tundra. Manual — part 2939

Fig. 131: Identifying Driving Mode Switching Pattern
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2. 2WD TO 4WD HIGH SWITCHING CONTROL (Pattern A)

1. CHANGE 4WD CONTROL SWITCH FROM 2WD TO 4H

2. 2WD-4WD TRANSFER SHIFT ACTUATOR MOTOR IS OPERATED

Fig. 132: Example Amperage Waveform Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

a. Vehicle speed judgment.

HINT:

When the vehicle speed is 100 km/h (62 mph) or more, vehicle speed limit violation control
is performed.

b. 2WD to 4WD HIGH switching vehicle speed limit violation control

VEHICLE SPEED LIMIT VIOLATION CONTROL

3. 4WD DETECTION SWITCH IS TURNED ON

Result

4WD DETECTION SWITCH RESULT REFERENCE

Control



Motor operation prohibited



4HI indicator light blinks at 0.5 seconds intervals



Warning buzzer sounds at 0.5 seconds intervals

Release of Control 4WD control switch: 2WD

Condition

Proceed

to

After 4WD control switch operation, detection switch turns ON within 10 seconds

A

2009 Toyota Tundra

2009 TRANSMISSION JF1A Transfer - Tundra

B: Go to step 7

A: Go to next step.

4. A.D.D. ACTUATOR MOTOR IS OPERATED

HINT:

When switching the A.D.D. actuator motor, the rotation difference limit violation control operates
when either of the following occurs: 1) there is a difference in the rotation of the front wheels and
rear wheels; or 2) there is a difference in the rotation of the front left wheel and front right wheel.

1. Rotation difference limit violation control

A.D.D. ACTUATOR MOTOR ROTATION DIFFERENCE LIMIT VIOLATION
CONTROL

5. A.D.D. ACTUATOR IS LOCKED (A.D.D. DETECTION SWITCH IS TURNED ON)

HINT:

If the A.D.D. actuator motor is performing the switch from 2WD to 4WD and then the 4WD
control switch is returned to 2WD, the 2WD switching operation is started after the 2WD to 4WD
switch completion.

6. 4HI INDICATOR LIGHT COMES ON

a. The 4HI indicator light comes on when the 2WD to 4WD HIGH switch is complete.

HINT:

If the 4WD control switch is changed to 4L before the 4WD HIGH switch completion,
switch prohibition control is performed.

1. Switch prohibition control

4HI INDICATOR LIGHT SWITCH PROHIBITION CONTROL

After 4WD control switch operation, detection switch does not turn ON even after 10
seconds have passed

B

Control



A.D.D. actuator motor operation prohibited



Warning buzzer sounds once (0.5 seconds on, 0.5 seconds off)

Release of
Control



Difference in rotation of front wheels and rear wheels: Less than
21.15 km/h (13.1 mph)



Difference in rotation of front left wheel and front right wheel: Less
than 5.5 km/h (3.4 mph)

2009 Toyota Tundra

2009 TRANSMISSION JF1A Transfer - Tundra

NEXT: END

7. 4WD HIGH TO 2WD RETURN CONTROL IS PERFORMED

a. 4WD HIGH to 2WD return control

4WD HIGH TO 2WD RETURN CONTROL

NEXT: END

3. 4WD HIGH TO 2WD SWITCHING CONTROL (Pattern B)

1. CHANGE 4WD CONTROL SWITCH FROM 4H TO 2WD

2. 2WD-4WD TRANSFER SHIFT ACTUATOR MOTOR IS OPERATED

a. Control is possible when driving at less than 100 km/h (62 mph).

HINT:

When the vehicle speed is 100 km/h (62 mph) or more, vehicle speed limit violation control
is performed.

1. 4WD HIGH to 2WD switching vehicle speed limit violation control

4WD HIGH TO 2WD SWITCHING VEHICLE SPEED LIMIT VIOLATION
CONTROL

Control



4LO indicator light blinks at 0.5 seconds intervals



Warning buzzer sounds at 0.5 seconds intervals

Release of Control 4WD control switch: Changed to position other than 4L

Control



4HI indicator light blinks at 0.5 seconds intervals



Switches to 2WD

Release of Control When 2WD switch completed

NOTE:



When the return control is completed, the 4WD control
switch is in the 4H position but the vehicle is in the 2WD
state, and this inconsistency causes the 4HI indicator light
to blink at 0.2 seconds intervals. Changing the 4WD
control switch to the 2WD position stops the blinking.



When the 4HI indicator light blinks at 0.2 seconds
intervals, the system is malfunctioning. Refer to the
PROBLEM SYMPTOMS TABLE .

Control



Motor operation prohibited



4HI indicator light blinks at 0.5 seconds intervals



Warning buzzer sounds at 0.5 seconds intervals

2009 Toyota Tundra

2009 TRANSMISSION JF1A Transfer - Tundra

3. 4WD DETECTION SWITCH IS TURNED OFF

4. A.D.D. ACTUATOR BECOMES FREE (A.D.D. DETECTION SWITCH IS TURNED OFF)

HINT:

If the A.D.D. actuator motor is performing the switch from 4WD to 2WD and then the 4WD
control switch is returned to 4H, the 4WD switching operation is started after the 4WD to 2WD
switch completion.

5. 4HI INDICATOR LIGHT TURNS OFF

a. The 4HI indicator light turns off when the 4WD HIGH to 2WD switch is complete.

HINT:

If the 4WD control switch is changed to 4L before the 2WD switch completion, switch
prohibition control is performed.

1. Switch prohibition control

4HI INDICATOR LIGHT SWITCH PROHIBITION CONTROL

NEXT: END

4. 4WD HIGH TO 4WD LOW SWITCHING CONTROL (Pattern C)

1. CHANGE 4WD CONTROL SWITCH FROM 4H TO 4L

2. HIGH-LOW TRANSFER SHIFT ACTUATOR MOTOR IS OPERATED

a. The high-low transfer shift actuator motor operates when all of the following conditions are

met: 1) the vehicle speed is less than 5 km/h (3 mph); 2) the shift lever is on N.

HINT:

When the conditions are not met, the 4WD HIGH to 4WD LOW switching violation control
operates.

1. 4WD HIGH to 4WD LOW switching violation control (if violation occurs after high-

low transfer shift actuator motor operation has started)

4WD HIGH TO 4WD LOW SWITCHING VIOLATION CONTROL

Release of Control 4WD control switch: 4H

Control



4LO indicator light blinks at 0.5 seconds intervals



Warning buzzer sounds at 0.5 seconds intervals

Release of Control 4WD control switch: Changed to position other than 4L



4LO indicator light blinks at 0.5 seconds intervals

2009 Toyota Tundra

2009 TRANSMISSION JF1A Transfer - Tundra