NOTE Perform the test at the normal operating ATF temperature of to C to F

a. D position test:

Shift into the D position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.

Check that the 1 --> 2, 2 --> 3, 3 --> 4 and 4 --> 5 up-shifts take place at the shift point shown in the automatic shift schedule (See ).

HINT:

5th Gear Up-shift Prohibition Control

• Engine coolant temperature is 55°C (131°F) or less and vehicle speed is at 32 mph (51 km/h) or less.

4th Gear Up-shift Prohibition Control

• Engine coolant temperature is 40°C (104°F) or less and vehicle speed is at 28 mph (45

2006 TRANSMISSION A750F Automatic Transaxle - Sequoia km/h) or less. 5th Gear Lock-up Prohibition Control

• Brake pedal is depressed.

• Accelerator pedal is released.

• Engine coolant temperature is 60°C (140°F) or less.

2. Check for shift shock and slippage.

Check for shock and slippage at the 1 --> 2, 2 --> 3, 3 --> 4 and 4 --> 5 up-shifts.

3. Check for abnormal noise and vibration.

Check for abnormal noise and vibration when up-shifting from 1 --> 2, 2 --> 3, 3 --> 4 and 4 --> 5 while driving with the shift lever in the D position, and check while driving in the lockup condition.

HINT:

The check for the cause of abnormal noise and vibration must be done thoroughly as it could also be due to loss of balance in the differential, torque converter clutch, etc.

4. Check kick-down operation.

Check vehicle speeds when the 2nd to 1st, 3rd to 2nd, 4th to 3rd, and 5th to 4th kick-downs take place while driving with the shift lever in the D position. Confirm that each speed is within the applicable vehicle speed range indicated in the automatic shift schedule (See ).

5. Check for abnormal shock and slippage at kick-down.

6. Check the lock-up mechanism.

• Drive in the D position (5th gear), at a steady speed (lock-up ON).

• Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.

HINT:

If there is a sudden increase in engine speed, there is no lock-up.

Shift into the 4 (O/D OFF) position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.

2006 TRANSMISSION A750F Automatic Transaxle - Sequoia

Check that the 1 --> 2, 2 --> 3, and 3 --> 4 upshifts take place and that the shift point conforms to the automatic shift schedule (See ).

HINT:

• There is no 5th up-shift in the 4 position.

• 4th Gear Lock-up Prohibition Control

■ Brake pedal is depressed.

■ Accelerator pedal is released.

■ Engine coolant temperature is 60°C (140°F) or less.

2. Check engine braking.

While driving in the 4 position and 4th gear, release the accelerator pedal and check the engine braking effect.

3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.

4. Check the lock-up mechanism.

• Drive in the 4 position and 4th gear, at a steady speed (lock-up ON).

• Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.

HINT:

If there is a sudden increase in engine speed, there is no lock-up. c. 3 position test

Shift into the 3 position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.

Check that the 1 --> 2 and 2 --> 3 up-shifts take place and that the shift point conforms to the automatic shift schedule (See ).

HINT:

• There is no 4th up-shift and lock-up in the 3 position.

• When the 2nd start switch is ON, there is no 1 --> 2 up-shift and 2 --> 1 down-shift.

2. Check engine braking.

While driving in the 3 position and 3rd gear, release the accelerator pedal and check the engine braking effect.

2006 TRANSMISSION A750F Automatic Transaxle - Sequoia

3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.

d. 2 position test

Shift into the 2 position and fully depress the accelerator pedal and check the following points.

1. Check up-shift operation.

Check that the 1 -- > 2 up-shift takes place and that the shift point conforms to the automatic shift schedule (See ).

HINT:

• There is no 3rd up-shift and lock-up in the 2 position.

• When the 2nd start switch is ON, there is no 1 --> 2 up-shift and 2 --> 1 down-shift.

2. Check engine braking.

While driving in the 2 position and 2nd gear, release the accelerator pedal and check the engine braking effect.

3. Check for abnormal noises during acceleration and deceleration, and for shock at up-shift and down-shift.

e. L position test

Shift into the L position and fully depress the accelerator pedal and check the following points.

1. Check no up-shift.

While driving in the L position, check that there is no up-shift to 2nd gear.

2. Check engine braking.

While driving in the L position, release the accelerator pedal and check the engine braking effect.

3. Check for abnormal noises during acceleration and deceleration.

f. R position test

Shift into the R position, lightly depress the accelerator pedal, and check that the vehicle moves backward without any abnormal noise or vibration.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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