LEXUS LS430 2003 Factory Repair Manual
Manufacturer: LEXUS, Model Year: 2003, Model line: LS430, Model: LEXUS LS430 2003Pages: 4500, PDF Size: 87.45 MB
Page 2791 of 4500

TABLE )
OK:
There are no foreign objects on each valve and they operate smoothly.
NG: REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSY (See step 6 on
REPLACEMENT
)
OK: Go to next step
4.INSPECT TORQUE CONVERTER CLUTCH ASSY (See INSPECTION
)
OK:
The torque converter clutch operates normally.
NG: REPLACE TORQUE CONVERTER CLUTCH ASSY
OK: REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSY (See COMPONENTS
)
DTC P0761: SHIFT SOLENOID "C" PERFORMANCE (SHIFT SOLENOID VALVE S3)
SYSTEM DESCRIPTION
The ECM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear
position (1st, 2nd, 3rd, 4th, 5th or 6th gear).
Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical
problems of the shift solenoid valves and valve body.
Page 2792 of 4500

Fig. 105: DTC Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
Gear positions in the event of a solenoid valve mechanical problem:
Fig. 106: Gear Position Specification
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Gear position during fail-safe operation:
If any malfunction is detected, the ECM changes into the fail-safe mode to shift into the gear positions as shown
in the table below.
Fig. 107: Gear Position Specification
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
MONITOR DESCRIPTION
This DTC indicates "stuck ON malfunction" or "stuck OFF malfunction" of the shift solenoid valve S3.
The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". When the gear position
commanded by the ECM and the actual gear position are not same, the ECM illuminates the MIL and stores the
DTC.
MONITOR STRATEGY
Page 2793 of 4500

Fig. 108: Monitor Strategy Specification Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
TYPICAL ENABLING CONDITIONS
The following items are common to all conditions below.
TYPICAL ENABLING CONDITIONS TABLE
OFF malfunction (A)
TYPICAL ENABLING CONDITIONS TABLE - OFF MALFUNCTION A
The monitor will run whenever this DTC is not
present.See LIST OF DISABLE A MONITOR
Turbine speed sensor circuitNot circuit malfunction
Output speed sensor circuitNot circuit malfunction
Shift solenoid valve S1 circuitNot circuit malfunction
Shift solenoid valve S2 circuitNot circuit malfunction
Shift solenoid valve S3 circuitNot circuit malfunction
Shift solenoid valve S4 circuitNot circuit malfunction
Shift solenoid valve SR circuitNot circuit malfunction
Shift solenoid valve SL1 circuitNot circuit malfunction
Shift solenoid valve SL2 circuitNot circuit malfunction
ECT (Engine coolant temperature) sensor circuitNot circuit malfunction
KCS sensor circuitNot circuit malfunction
ETCS (Electric throttle control system)Not system down
Transmission range"D"
ECT40°C (104°F) or more
Spark advance from Max. retard timing by KCS
control0° CA or more
EngineStarting
ECM selected gear2nd
Page 2794 of 4500

OFF malfunction (B)
TYPICAL ENABLING CONDITIONS TABLE - OFF MALFUNCTION B
ON malfunction (A)
TYPICAL ENABLING CONDITIONS TABLE - ON MALFUNCTION A
ON malfunction (B)
TYPICAL ENABLING CONDITIONS TABLE - ON MALFUNCTION B
ON malfunction (C)
TYPICAL ENABLING CONDITIONS TABLE - ON MALFUNCTION C
TYPICAL MALFUNCTION THRESHOLDS
[OFF malfunction]
Both of the following conditions are met: OFF malfunctions (A) and (B)
OFF malfunction (A)
Vehicle speed2 km/h (1.2 mph) or more
Output speed2nd --> 1st down shift point or more
Throttle valve opening angle6.5% or more at 2,000 rpm (Conditions vary with
engine speed)
ECM selected gear6th
Vehicle speed2 km/h (1.2 mph) or more
Throttle valve opening angle6.5% or more at 2,000 rpm (Conditions vary with
engine speed)
ECM selected gear4th
Vehicle speed2 km/h (1.2 mph) or more
Throttle valve opening angle6.5% or more at 2,000 rpm (Conditions vary with
engine speed)
Current ECM selected gear5th
Last ECM selected gear4th
Vehicle speed (During transition from 4th to 5th
gear)Less than 100 km/h (62.2 mph)
ECM selected gear5th
Engine speed - Turbine speed (NE - NT) (After
transition to 5th gear)Less than 150 rpm
Vehicle speed (After transition to 5th gear)Less than 100 km/h (62.2 mph)
Page 2795 of 4500
![LEXUS LS430 2003 Factory Repair Manual TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION A
OFF malfunction (B)
TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION B
[ON malfunction]
One of the following conditions is met: ON LEXUS LS430 2003 Factory Repair Manual TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION A
OFF malfunction (B)
TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION B
[ON malfunction]
One of the following conditions is met: ON](/img/36/57050/w960_57050-2794.png)
TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION A
OFF malfunction (B)
TYPICAL MALFUNCTION THRESHOLDS TABLE - OFF MALFUNCTION B
[ON malfunction]
One of the following conditions is met: ON malfunctions (A), (B) and (C)
ON malfunction (A)
TYPICAL MALFUNCTION THRESHOLDS TABLE - ON MALFUNCTION A
ON malfunction (B)
TYPICAL MALFUNCTION THRESHOLDS TABLE - ON MALFUNCTION B
ON malfunction (C)
TYPICAL MALFUNCTION THRESHOLDS TABLE - ON MALFUNCTION C
INSPECTION PROCEDURE
HINT:
Performing the ACTIVE TEST using the hand-held tester allows the relay, VSV, actuator and so on to operate
without parts removal. Performing the ACTIVE TEST as the first step of troubleshooting is one method to
shorten labor time.
It is possible to display the DATA LIST during the ACTIVE TEST.
a. Warm up the engine.
b. Turn the ignition switch off.
c. Connect the han
d-held tester together with the CAN VIM (controller area network vehicle interface
Turbine speed/Output speed (NT/NO)0.93 or more and 1.07 or less (This means actual
gear is 3rd)
Turbine speed/Output speed (NT/NO)0.50 or more and 0.64 or less (This means actual
gear is 6th)
Turbine speed/Output speed (NT/NO)1.23 or more and 1.48 or less (This means actual
gear is 3rd)
Turbine speed - Output speed x 4th gear ratio (NT-
NO x 4th gear ratio)1,000 rpm or more
Turbine speed - Output speed x 5th gear ratio (NT-
NO x 5th gear ratio)1,000 rpm or more
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module) to the DLC3.
d. Turn the ignition switch to the ON position.
e. Push the "ON" button of the hand-held tester.
f. Clear the DTC.
g. Select the item "DIAGNOSIS/ENHANCED OBD II/ACTIVE TEST/SHIFT".
h. According to the display on tester, perform the "ACTIVE TEST"
HINT:
While driving, the shift position can be forcibly changed with the hand-held tester.
Comparing the shift position commanded by the ACTIVE TEST with the actual shift position enables you to
confirm the problem (see FAIL
-SAFE CHART ).
Fig. 109: Test Item Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
The 4th to 5th and 5th to 6th up-shiftings must be performed with the accelerator pedal released.
The 6th to 5th and 5th to 4th down-shiftings must be performed with the accelerator pedal released.
Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.
The shift position commanded by the ECM is shown in the DATA LIST/SHIFT display on the hand-held
tester.
<0037004b004800030056004b004c00490057000300560052004f004800510052004c0047000300590044004f005900480003003600160003004c00560003005700580055005100480047000300520051001200520049004900030051005200550050004400
4f004f005c0003005a004b0048005100030057004b00480003[shift lever is in the D position:
GEARSHIFT SPECIFICATION TABLE
ECM
command
gearshift
1st2nd3rd4th5th6th
Shift solenoid
valve S3ONONONOFFOFFOFF
Page 2797 of 4500

1.CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0761)
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position and push the hand-held tester main switch ON.
c. Select the item "DIAGNOSIS/ENHANCED OBD II/DTC INFO/CURRENT CODES".
d. Read the DTCs using the hand-held tester.
Result:
DTC OUTPUT RESULT TABLE
HINT:
If any other codes besides "P0761" are output, perform troubleshooting for those DTCs first.
B: GO TO RELEVANT DTC CHART (See DIAGNOSTIC TROUBLE CODE CHART
)
A: Go to next step
2.PERFORM ACTIVE TEST BY HAND - HELD TESTER
SST 09992-00095 (09992-00231, 09992-00271)
HINT:
Performing the intelligent tester's ACTIVE TEST allows relay, VSV, actuator and other items to be
operated without removing any parts. Performing the ACTIVE TEST early in troubleshooting is one way
to save time. The DATA LIST can be displayed during the ACTIVE TEST.
a. Remove the test plu
g on the transmission case center right side and connect SST.
Display (DTC output)Proceed to
Only "P0761" is outputA
"P0761" and other DTCsB
Page 2798 of 4500

Fig. 110: Measuring Line Pressure With SST
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Connect the hand - held tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
Page 2799 of 4500

c. Start the engine and warm it up.
d. Measure the line pressure with SST.
e. Turn the hand - held tester ON.
f. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST.
g. Follow the instructions on the tester and perform the ACTIVE TEST.
h. Measure the line pressure with SST.
ITEM DIAGNOSTIC NOTE CHART
NG: REPLACE SHIFT SOLENOID VALVE SLT
OK: GO TO NEXT STEP
3.INSPECT SHIFT SOLENOID VALVE (S3)
a. Remove the shift solenoid valve S3.
b. Measure the resistance according to the value(s) in the table below.
Standard:
SHIFT SOLENOID VALVE (S3) - RESISTANCE TABLE
ItemTest DetailsDiagnostic Note
LINE PRESS UP(1)
[Test Details]
Operate shift solenoid SLT and
raise line pressure
[Vehicle Condition]
Vehicle stopped
IDL: ON
HINT:
OFF: Line pressure up (when
Active Test "LINE PRESS UP" is
performed, ECM commands SLT
solenoid to turn OFF)
ON: No action (normal operation)
-
HINT:
The pressure values in ACTIVE TEST and HYDRAULIC TEST are different from each other.
Normally, the line pressure detected in the ACTIVE TEST is approximately half of the value
detected in the HYDRAULIC TEST's stall test.
(1)"LINE PRESS UP" in the ACTIVE TEST is performed to check the line pressure change by
connecting SST to the automatic transmission, which is used in the HYDRAULIC TEST
(see )
Page 2800 of 4500

c. Connect positive (+) lead to the terminal of solenoid connector, negative (-) lead to the solenoid
body.
OK:
The solenoid makes an operating noise.
Fig. 111: Inspecting Shift Solenoid Valve (S3)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE SHIFT SOLENOID VALVE (S3)
OK: Go to next step
4.INSPECT TRANSMISSION VALVE BODY ASSY (See chapter 2 in PROBLEM SYMPTOMS
TABLE )
OK:
Tester ConnectionSpecified Condition 20°C(68°F)
Solenoid Connector (S3) - Solenoid Body (S3)11 to 15ohms