Lexus SC300 / Lexus SC400. Manual - part 73

(f) Check the fluid level at the normal operating temperature

70–80

C (158–176

F) and add as necessary.

NOTICE: Do not overfill.

CHECK FLUID LEAKS
Check for leaks in the transmission.
If there are leaks, it is necessary to repair or replace O–rings,
seal packings, oil seals, plugs or other parts.

INSPECT AND ADJUST THROTTLE CABLE

(a) Remove the 2 bolts, nut and throttle body cover.

(b)  Check that the throttle valve is fully closed.
(c)  Check that the inner cable is not slack.
(d)  Measure the distance between the outer cable end and

stopper on the cable.

Standard distance:

0–1 mm (0–0.04 in.)

If the distance is not standard, adjust the cable by the adjust-
ing nuts.

(e) Install the throttle body cover, and two bolts and nut.

INSPECT AND ADJUST SHIFT LEVER POSITION
When shifting the shift lever from the N position to other posi-
tions, check that the lever can be shifted smoothly and accu-
rately to each position and that the position indicator correctly
indicates the position.
If the indicator is not aligned with the correct position, carry
out the following adjustment procedures:

(a)  Loosen the nut on the control shaft lever.
(b)  Push the control shaft lever fully rearward.
(c)  Return the control shaft lever 2 notches to N position.
(d)  Set the shift lever to N position.
(e) While

holding

the shift lever lightly toward the R position side,

tighten the shift lever nut.

(f) Start the engine and make sure that the vehicle moves

forward when shifting the lever from the N to D position and
reverses when shifting it to the R position.

AT–48

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING

7. INSPECT

AND

ADJUST

PARK/NEUTRAL POSITION

SWITCH
Check that the engine can be started with the shift lever only
in the N or P position, but not in other positions.
If not as started above, carry out the following adjustment
procedure:

(a) Loosen the park/neutral position switch bolt and set the shift

lever to the N position.

(b) Align the groove and neutral basic line.
(c) Hold in position and tighten the bolt.

Torque: 12 N

⋅

m (125 kgf

⋅

cm, 9 ft

⋅

lbf)

For continuity inspection of the park/neutral position switch,
see page AT–106.

INSPECT IDLE SPEED

Idle speed:

650 RPM (In N position and air conditioner OFF)

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

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AT–49

MECHANICAL SYSTEM TESTS

AT0QT–01

STALL TEST

The object of this test is to check the overall performance of the transmission and engine by measuring
the stall speeds in the D and R positions.
NOTICE:

Perform the test at normal operating fluid temperature 50–80

C (122–176

F).

Do not continuously run this test longer than 5 seconds.

To ensure safety, conduct this test in a wide, clear, level area, which provides good traction.

The stall test should always be carried out in pairs. One technician should observe the conditions of

wheels or wheel stoppers outside the vehicle while the other is performing the test.

MEASURE STALL SPEED
(a)  Chock the 4 wheels.
(b)  Connect a tachometer to the engine.
(c)  Fully apply the parking brake.
(d)  Keep your left foot pressed firmly on the brake pedal.
(e)  Start the engine.
(f)

Shift into the D position. Step all the way down on the accelerator pedal with your right foot.
Quickly read the stall speed at this time.

Stall speed:

2,200

150 RPM

(g) Perform the same test in R position.

AT–50

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A304E (1UZ–FE) AUTOMATIC TRANSMISSION

TROUBLESHOOTING

EVALUATION

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Problem

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Possible cause

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Engine output may be insufficient.

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Stator one–way clutch is operating properly

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(a) Stall speed low in D and R positions.

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HINT:

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If more than 600 RPM below the specified value, the

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torque converter could be faulty.

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Line pressure too low

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(b) Stall speed high in D position

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Forward clutch slopping

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(b) Stall speed high in D position.

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No.2 one–way clutch not operating properly

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O/D one–way clutch not operating properly

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Line pressure too low

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Direct clutch slipping

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First and reverse brake slipping

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O/D one–way clutch not operating properly

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Line pressure too low

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(d) Stall speed high in D and R position.

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Improper fluid level

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O/D one–way clutch not operating properly

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AT–51

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