Identifying condition LEXUS LS430 2003 Factory Repair Manual
Page 1843 of 4500
c. Check the deflection width of the speedometer indicator.
Reference: Below 0.5 km/h (0.3 mph)
2.INSPECT OUTPUT OF VEHICLE SPEED
a. Check the output signal waveform.
1. Remove the combination meter assy.
2. Connect the oscilloscope to terminal C12-19 and body ground.
3. Start the engine.
Fig. 87: Identifying Terminal C12
-19
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
4. Check the signal waveform according to the condition (s) in the table below.
SIGNAL WAVEFORM CONDITIONS
ItemCondition
Tool setting5 V/DIV, 20 ms/DIV
Page 1844 of 4500
OK:
As shown in the illustration
HINT:
As vehicle speed increases, the cycle of the signal waveform narrows.
Fig. 88: Identifying Signal Waveform
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
3.INSPECT TACHOMETER
a. Check operation
b. Connect the tune-up test tachometer and start the engine.
Vehicle conditionDriving at approx. 20 Km/h (12 mph)
Page 1916 of 4500
Fig. 12: Identifying DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DLC3 CONNECTOR TERMINALS RESISTANCE SPECIFICATION
HINT:
If the displa
y shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the
Symbols (Terminals No.)Terminal DescriptionConditionSpecified Condition
SIL(7) - SG(5)Bus "+" lineDuring transmissionPulse generation
CG(4) - Body groundChassis groundAlwaysBelow 1 ohms
SG(5) - Body groundSignal groundAlwaysBelow 1 ohms
BAT(16) - Body groundBattery positiveAlways11 to 14 V
CANH(6) - CANL(14)HIGH-level CAN bus lineIG switch OFF54 to 67 ohms
CANH(6) - Battery positiveHIGH-level CAN bus lineIG switch OFF1 Mohms or higher
CANH(6) - CG(4)HIGH-level CAN bus lineIG switch OFF3 kohms or higher
CANL(14) - Battery positiveLOW-level CAN bus lineIG switch OFF1 Mohms or higher
CANL(14) - CG(4)LOW-level CAN bus lineIG switch OFF3 kohms or higher
Page 1926 of 4500
Fig. 21: Identifying Stop Lamp Switch Assy Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
3.CHECK HARNESS AND CONNECTOR (STOP LAMP SWITCH - BATTERY)
a. Measure the voltage according to the value(s) in the table below.
STOP LAMP SWITCH TERMINALS VOLTAGE SPECIFICATION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Tester connectionConditionSpecified condition
S19-2 - Body groundAlways10 to 14 V
S19-3 - Body groundIgnition SW ON10 to 14 V
Page 1927 of 4500
Fig. 22: Identifying Stop Lamp Switch Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
4.INSPECT ECM
a. Reconnect the stop lamp switch connector.
b. Disconnect the E2 and E3 connectors from the ECM.
c. Turn the ignition switch to the ON position.
d. Measure the voltage according to the value(s) in the table below.
ECM CONNECTOR TERMINALS VOLTAGE RESISTANCE SPECIFICATION
RESULT DETAIL
Pedal conditionTester connectionSpecification
DepressedE2-4 (STP) - Body ground10 to 14 V
ReleasedE2-4 (STP) - Body groundBelow 1 V
DepressedE3-8 (ST1-) - Body groundBelow 1 V
ReleasedE3-8 (ST1-) - Body ground10 to 14 V
Page 1930 of 4500
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A: REPLACE ECM (SEE REPLACEMENT
)
5.INSPECT DRIVER SIDE J/B
a. Measure the voltage according to the value(s) in the table below.
Fig. 24: Identifying Driver Side Junction Block ECU Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DRIVER SIDE JUNCTION BLOCK ECU TERMINALS VOLTAGE SPECIFICATION
NG: Go to step 6
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVER SIDE J/B ECU - ECM)
6.INSPECT DRIVER SIDE J/B
Pedal conditionTester connectionSpecification
DepressedD3-12 (STPO) - Body ground10 to 14 V
ReleasedD3-12 (STPO) - Body groundBelow 1 V
Page 1931 of 4500
a. Measure the voltage according to the value(s) in the table below.
Fig. 25: Identifying Driver Side Junction Block ECU Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DRIVER SIDE JUNCTION BLOCK ECU TERMINALS VOLTAGE SPECIFICATION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LAMP SWITCH - DRIVER
SIDE J/B ECU)
OK: REPLACE DRIVER SIDE J/B
CIRCUIT DESCRIPTION
Pedal conditionTester connectionSpecification
DepressedD3-12 (STPI) - Body ground10 to 14 V
ReleasedD3-12 (STPI) - Body groundBelow 1 V
Page 1934 of 4500
Fig. 27: Identifying Cruise Control Main Switch Positions
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HAND-HELD TESTER VALUE (ECM)
OK: When cruise control main switch operation is performed the standard values will be above.
RESULT DETAIL
Item
Measurement Item /
Display (Range)
Normal ConditionDiagnostic Note
MAIN SW (MAIN)Main SW signal (Main
CPU) / ON or OFFON: Main SW ON (Pushed on)
OFF Main SW OFF (Pushed off)-
MAIN SW (SUB)Main SW signal (Main
CPU) / ON or OFFON: Main SW ON (Pushed on)
OFF Main SW OFF (Pushed off)-
CANCEL SWCANCEL SW signal / ON or
OFFON: CANCEL SW ON OFF:
CANCEL SW OFF-
SET/COAST SWSET/COAST SW signal / ON
or OFFON: SET/COAST SW ON OFF:
SET/COAST SW OFF-
RES/ACC SWRES/ACC SW signal / ON or
OFFON: RES/ACC SW ON OFF:
RES/ACC OFF-
Page 1942 of 4500
1.CHECK HARNESS AND CONNECTOR (TC of DLC3 - ECM)
a. Disconnect the E2 connector from the ECM.
b. Measure the resistance according to the value(s) in the table below.
DLC3 CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Fig. 33: Identifying DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Tester connectionConditionSpecified condition
TC (E2-3) - TC (D1 - 13)AlwaysBelow 1 ohms
Page 1944 of 4500
Fig. 34: Disconnecting E2 Connector From ECM
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (DLC3 - ECM)
OK: Go to next step
2.CHECK HARNESS AND CONNECTOR (CG of DLC3 - BODY GROUND)
a. Measure the resistance according to the value(s) in the table below.
DLC3 CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Fig. 35: Identifying DLC3 Connector (CG) Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (DLC3 - BODY GROUND)
OK: Go to next step
Tester connectionConditionSpecified condition
CG (D1-4) - Body groundAlwaysBelow 1 ohms