sensor LEXUS LS430 2003 Factory Repair Manual

This function minimizes the loss of the ECT functions when any malfunction occurs in each sensor or
solenoid.
Fig. 40: Identifying Fail
-Safe Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
*1: Al (Artificial Intelligence) -SHIFT control
In addition to the switching of the shift pattern through the pattern select switch, the AI-SHIFT control
enables the ECM to estimate the road conditions and the driver's intention in order to automatically select
the optimal shift pattern. As a result, a comfortable ride has been realized.
a. Fail-safe operation for electronically malfunctioning shift solenoid valve (S1, S2, S3, S4 and SR):
HINT:
Fail-safe operation in the event of an electric system malfunction.
Fail safe function:
If either of the shift solenoid valve circuits has an open or short failure, the ECM turns the other
shift solenoid "ON" and "OFF" in order to shift into the gear positions shown in the table below.
In case of a short circuit, the ECM stops sending current to the short circuited solenoid.
Even if starting the engine again in the fail-safe mode, the gear position remains in the same
position.

b. Fail-safe operation for mechanically malfunction:
HINT:
Fail-safe operation in the event of a mechanical system malfunction.
Fail safe function:
The ECM controls the gear position as shown in the table below when malfunctions occur.
Fig. 43: Identifying Mechanical Malfunction Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DATA LIST/ACTIVE TEST
1.DATA LIST
HINT:
According to the DATA LIST displayed by the hand-held tester, you can read the value of the switch,
sensor, actuator and so on without parts removal. Reading the DATA LIST as the first step of
troubleshooting is one method to shorten labor time.

Fig. 46: Test Item Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
The pressure values in ACTIVE TEST and HYDRAULIC TEST are different from each other.
DIAGNOSTIC TROUBLE CODE CHART
If a DTC is displayed during the DTC check, check the parts listed in the table below.
DTC LIST
DTCDescription
DTC P0705, P0850TRANSMISSION RANGE SENSOR CIRCUIT
MALFUNCTION (PRNDL INPUT),
PARK/NEUTRAL SWITCH INPUT CIRCUIT
DTC P0710, P0712, P0713TRANSMISSION FLUID TEMPERATURE
SENSOR "A" CIRCUIT LOW/HIGH INPUT
DTC P0711TRANSMISSION FLUID TEMPERATURE
SENSOR "A" PERFORMANCE
DTC P0717TURBINE SPEED SENSOR CIRCUIT NO SIGNAL
DTC P0724BRAKE SWITCH "B" CIRCUIT HIGH
DTC P0729GEAR 6 INCORRECT RATIO
DTC P0748PRESSURE CONTROL SOLENOID "A"
ELECTRICAL (SHIFT SOLENOID VALVE SL1)

Fig. 48: Diagnostic Trouble Code Reference Chart (2 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DTC P0705, P0850: TRANSMISSION RANGE SENSOR CIRCUIT MALFUNCTION (PRNDL INPUT),
PARK/NEUTRAL SWITCH INPUT CIRCUIT

P0850:
MONITOR STRATEGY TABLE - P0850
TYPICAL ENABLING CONDITIONS
P0705:
TYPICAL ENABLING CONDITIONS TABLE - P0705
P0850:
All of following conditions are met
TYPICAL ENABLING CONDITIONS TABLE - P0850
TYPICAL MALFUNCTION THRESHOLDS
P0705:
Required sensors/ComponentsPark/neutral position switch
Frequency of operationContinuous
DurationCondition (A) and (B) 2 sec. Condition (C) 60 sec.
MIL operation2 driving cycles
Sequence of operationNone
Related DTCsP0850: Park/neutral position switch/Verify switch
input
Required sensors/ComponentsPark/neutral position switch
Frequency of operationContinuous
Duration30 sec.
MIL operation2 driving cycle
Sequence of operationNone
The monitor will run whenever this DTC is not
present.See LIST OF DISABLE A MONITOR
Ignition switchON
Battery voltage10.5 V or more
The monitor will run whenever this DTC is not
present.See LIST OF DISABLE A MONITOR
Vehicle speed70 km/h (43.47 mph) or more
Engine speed1,000 rpm or more and 2,500 rpm or less
Intake air amount per revolution0.8 g/rev or more
Battery voltage8 V or more
Ignition switchON
StarterOFF

According to the DATA LIST displayed by the hand-held tester, you can read the value of the switch, sensor,
actuator and so on without parts removal. Reading the DATA LIST as the first step of troubleshooting is one
method to shorten labor time.
a. Turn the ignition switch off.
b. Connect the hand-held tester together with the CAN VIM (controller area network vehicle interface
module) to the DLC3.
c. Turn the ignition switch to the ON position.
d. Push the "ON" button of the OBD II scan tool or the hand-held tester.
e. Select the item "DIAGNOSIS/ENHANCED OBD II/DATA LIST".
f. According to the display on tester, read the "DATA LIST".
Fig. 51: Test Item Reference Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.INSPECT PARK/NEUTRAL POSITION SWITCH ASSY
a. Disconnect the park/neutral position switch connector.
b. Measure resistance according to the value(s) in the table below when the shift lever is moved to
each position.

Fig. 57: ECM Connector Terminals Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (SeeELECTRONIC CIRCUIT
INSPECTION PROCEDURE )
OK: REPLACE ECM (See REPLACEMENT
)
DTC P0710, P0712, P0713: TRANSMISSION FLUID TEMPERATURE SENSOR "A" CIRCUIT
LOW/HIGH INPUT
CIRCUIT DESCRIPTION
The ATF (Automatic Transmission Fluid) temperature sensor converts the fluid temperature into a resistance
value which is input into the ECM.
The ECM applies a voltage to the temperature sensor through ECM terminal OIL.
The sensor resistance changes with the transmission fluid temperature. As the temperature becomes higher, the
sensor resistance decreases.
One terminal of the sensor is grounded so that the sensor resistance decreases and the voltage goes down as the
temperature becomes higher.
The ECM calculates the fluid temperature based on the volta
ge signal.

Fig. 59: DTC Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
MONITOR DESCRIPTION
These DTCs indicate an open or short in the automatic transmission fluid (ATF) temperature sensor circuit. The
automatic transmission fluid (ATF) temperature sensor converts ATF temperature to an electrical resistance
value. Based on the resistance, the ECM determines the ATF temperature, and the ECM detects an opens or
shorts in the ATF temperature circuit. If the resistance value of the ATF temperature is less than 79ohms*1 or
more than 156kohms*2, the ECM interprets this as a fault in the ATF sensor or wiring. The ECM will turn on
the MIL and store the DTC.
*1: 150°C (302°F) or more is indicated regardless of the actual ATF temperature.
*2: -40°C (-40°F) is indicated regardless of the actual ATF temperature.
HINT:
The ATF temperature can be checked on the OBD II scan tool or hand-held tester display.
MONITOR STRATEGY
MONITOR STRATEGY TABLE
Related DTCsP0710: ATF temperature sensor/Range check
(Chattering) P0712: ATF temperature
sensor/Range check (Low resistance) P0713: ATF
temperature sensor/Range check (High resistance)
Required sensors/ComponentsATF temperature sensor (TFT sensor)
Frequency of operationContinuous
Duration0.5 sec.
MIL operationImmediate
Sequence of operationNone

TYPICAL ENABLING CONDITIONS
P0710: Range check (Chattering)
P0712: Range check (Low resistance)
TYPICAL ENABLING CONDITIONS TABLE - P0710, P0712
P0713: Range check (High resistance)
TYPICAL ENABLING CONDITIONS TABLE - P0713
TYPICAL MALFUNCTION THRESHOLDS
P0710: Range check (Chattering)
TYPICAL MALFUNCTION THRESHOLDS TABLE - P0710
P0712: Range check (Low resistance)
TYPICAL MALFUNCTION THRESHOLDS P0712
P0713: Range check (High resistance)
TYPICAL MALFUNCTION THRESHOLDS TABLE - P0713
COMPONENT OPERATING RANGE
COMPONENT OPERATING RANGE TABLE
WIRING DIAGRAM
The monitor will run whenever these DTCs are not
present.See LIST OF DISABLE A MONITOR
The typical enabling condition is not available.-
The monitor will run whenever this DTC is not
present.See LIST OF DISABLE A MONITOR
Time after engine start15 min. or more
TFT (transmission fluid temperature) sensor
resistanceLess than 79 ohms or More than 156 kohms
TFT sensor resistanceLess than 79ohms
TFT sensor resistanceMore than 156 kohms
TFT sensorAtmospheric temperature - approx. 130°C (266° F)

Fig. 60: DTCs P0710, P0712, P0713 - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
HINT:
According to the DATA LIST displayed by the hand-held tester, you can read the value of the switch, sensor
actuator and so on without parts removal. Reading the DATA LIST as the first step of troubleshooting is one
method to shorten labor time.
a. Warm up the engine.
b. Turn the ignition switch off.
c. Connect the hand-held tester together with the CAN VIM (controller area network vehicle interface
module) to the DLC3.
d. Turn the ignition switch to the ON position.
e. Push the "ON" button of the hand-held tester.
f. Select the item "DIAGNOSIS/ENHANCED OBD II/DATA LIST".
g. According to the display on tester, read the "DATA LIST".