2003 LEXUS LS430 Ecm

OK:
The torque converter clutch operates normally.
NG: REPLACE TORQUE CONVERTER CLUTCH ASSY
OK: REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSY (See COMPONENTS
)
DTC P0756: SHIFT SOLENOID "B" PERFORMANCE (SHIFT SOLENOID VALVE S2)
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.
Fig. 101: 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. 102: 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 S2.
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
MONITOR STRATEGY TABLE
TYPICAL ENABLING CONDITIONS
The following items are common to all conditions below.
TYPICAL ENABLING CONDITIONS TABLE
Related DTCsP0756: Shift solenoid valve S2/OFF malfunction
Shift solenoid valve S2/ON malfunction
Required sensors/ComponentsShift solenoid valve S2
Frequency of operationContinuous
Duration0.4 sec.
MIL operation2 driving cycles
Sequence of operationNone
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

OFF malfunction (A)
TYPICAL ENABLING CONDITIONS TABLE - OFF MALFUNCTION A
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
TYPICAL MALFUNCTION THRESHOLDS
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 gear1st
Vehicle speed2 km/h (1.2 mph) or more and Less than 40 km/h
(24.9 mph)
Engine speed-Turbine speed (NE-NT)50 rpm or more
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 gear5th
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 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)

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. 103: 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.
<0037004b004800030056004b004c00490057000300560052004f004800510052004c0047000300590044004f005900480003003600150003004c00560003005700580055005100480047000300520051001200520049004900030051005200550050004400
4f004f005c0003005a004b0048005100030057004b00480003[shift lever is in the D position:
GEARSHIFT SPECIFICATION TABLE
1.CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0756)
ECM
command
gearshift
1st2nd3rd4th5th6th
Shift solenoid
valve S2ONONOFFOFFOFFON

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.

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

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

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)