2003 LEXUS LS430 sensor

Fig. 198: Transmission Control Switch Reference Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (See ELECTRONIC CIRCUIT
INSPECTION PROCEDURE )
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
PATTERN SELECT SWITCH CIRCUIT (PWR)
CIRCUIT DESCRIPTION
Passenger side J/B ECU receives pattern select switch information, and sends it through the multiplex
communication system and CAN system to the ECM.
The ECM memory contains the shift programs for the NORMAL, POWER and SNOW patterns, 2 position, L
position and the loc
k-up patterns. By following the programs corresponding to the signals from the pattern
select switch, the neutral start and other various sensors, the ECM switches the solenoid valves ON and OFF,
and controls the transmission gear change and the lock-up clutch operation.
WIRING DIAGRAM

LS 430
CEC
Computerized Engine Controls
EVAP
Fuel Evaporative System
EVAP-CCVVSV
EVAP Canister Closed Valve Vacuum Switching Valve
EVAP-VC
EVAP Vapor Canister
EVAP-VPS
EVAP Vapor Pressure Sensor
EVAP-VPSVSV
Vapor Pressure Sensor Vacuum Switching Valve
Engine & Fuel System(1) Emission Control Systems & Devices
2006

4.3L (261") V8 SFIPCV, EVAP, (2) TWC, FR, SPK, (3) HO2S, CEC,
MIL, EVAP-VSV, EVAP-VC, EVAP-VPS, EVAP-
VPSVSV, EVAP-CCVVSV, ORVR-COV, ORVR-
OCKV
(1)For quick reference, major emission control systems and devices are listed in bold type; components
and other related devices are listed in light type.
(2)Equipped with 3.
(3)Equipped with 4.

EVAP-VSV
EVAP Vacuum Switching Valve
FR
Fill Pipe Restrictor
HO2S
Heated Oxygen Sensor
MIL
Malfunction Indicator Light
ORVR-COV
On-Board Refueling Vapor Recovery Cut-Off Valve
ORVR-OCKV
On-Board Refueling Vapor Recovery Overfill Check Valve
PCV
Positive Crankcase Ventilation
SFI
Sequential Multiport Fuel Injection
SPK-CC
SPK Computer Controlled
TWC
Three-Way Catalytic Converter
WU-TWC
Warm-Up Three-Wa
y Catalytic Converter

c. Warm up the heated oxygen sensor with the engine speed at 2,500 rpm for approximately 2
minutes.
d. Check that the voltage changes between 0 and 1 V with the engine speed at 2,500 rpm.
OK: The voltage has changed more than 8 times in 10 seconds.
Fig. 6: Inspecting A/F Compensation System

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2.INSPECT FUEL CUT OFF RPM
a. Increase the engine speed to at least 3,000 rpm.
b. Use a sound scope to check the injector operation noise.
OK: When the throttle lever is released, the injector operation noise stops momentarily but
starts again soon after.

Fig. 8: Checking Cracks, Leaks Or Damage
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5.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
a. Bank 1 sensor 1, bank 2 sensor 1:
Disconnect the sensor connector.
b. Measure the resistance between terminals 1 (HT) and 2 (+B).
Standard:
RESISTANCE CONDITION
If the result is not as specified, replace the sensor.
ConditionSpecified Condition
20°C (68°F)11 to 16 ohms

Fig. 9: Identifying Connector Terminals Heated Oxygen Sensor
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
c. Bank 1 sensor 2, bank 2 sensor 2:
Disconnect the sensor connector.
d. Measure the resistance between terminals 1 (HT) and 2 (+B).
Standard:
RESISTANCE CONDITION
If the result is not as specified, replace the sensor.
ConditionSpecified Condition
20°C (68°F)11 to 16 ohms

Fig. 10: Identifying Connector Terminals Heated Oxygen Sensor
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION
1.INSPECT CHARCOAL CANISTER ASSY
a. Visually check the charcoal canister for cracks or damage.
If cracks or damage are found, replace the canister.

SYSTEM DIAGRAM
Engine control system is determined by the ECM based on signals from various sensors.
Fig. 2: Engine Control
- System Diagram
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