2003 LEXUS LS430 Identifying condition

Fig. 45: 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.
Standard:
STOP LAMP SWITCH TERMINALS VOLTAGE SPECIFICATION
Tester connectionConditionSpecified condition
S19-2 - Body groundAlways10 to 14 V
S19-3 - Body groundIgnition SW ON10 to 14 V

Fig. 46: Identifying Stop Lamp Switch Assy Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
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.
Standard:
ECM TERMINALS VOLTAGE SPECIFICATION
Pedal conditionTester connectionSpecification
DepressedE2-4 (STP) - Body ground10 to 14 V
ReleasedE2-4 (STP) - Body groundBelow 1 V

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
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. 48: Identifying Driver Side Junction Block ECU Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Standard:
ECU CONNECTOR VOLTAGE RESISTANCE SPECIFICATION
NG: Go to step 6
Pedal conditionTester connectionSpecification
DepressedD3-12 (STPO) - Body ground10 to 14 V
ReleasedD3-12 (STPO) - Body groundBelow 1 V

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (DRIVER SIDE J/B ECU -
ECM)
6.INSPECT DRIVER SIDE J/B
a. Measure the voltage according to the value(s) in the table below.
Fig. 49: Identifying Driver Side Junction Block ECU Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Standard:
ECU CONNECTOR TERMINALS VOLTAGE SPECIFICATION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (STOP LAMP SWITCH -
DRIVER SIDE J/B ECU)
Pedal conditionTester connectionSpecification
DepressedD3-13 (STPI) - Body ground10 to 14 V
ReleasedD3-13 (STPI) - Body groundBelow 1 V

Fig. 59: Identifying Laser Sensor Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
c. Check the signal waveform between terminal LRDD (L1-3) of the laser sensor and body ground.
OK:
A waveform similar to that in the illustration to the left is output.
HINT:
Gauge set: 1 V/DIV, 2 ms/DIV
Condition: Ignition switch ON
NG: REPLACE LASER SENSOR (SEE REPLACEMENT
)

Fig. 65: Identifying Cruise Control ECU Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
d. Check the signal waveform between terminal LRRD (D2-23) of the cruise control ECU (distance
control ECU) and body ground.
OK:
A waveform similar to that in the illustration to the left is output.
HINT:
Gauge set: 2 V/DIV, 5 ms/DIV
Condition: Ignition switch ON
NG: REPLACE CRUISE CONTROL ECU ASSY (SEE REPLACEMENT
)

a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. According to the display on the tester, read the "DATA LIST".
Fig. 78: Identifying Cruise Control Main Switch Position

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
CC (ECM):
DATA LIST (CC (ECM))
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 (Sub 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-

OK: Go To Next Step.
4.CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSY - ECM)
a. Measure the resistance according to the value(s) in the table below.
Standard:
SPIRAL CABLE SUB-ASSY AND ECM TERMINALS RESISTANCE SPECIFICATION
Fig. 81: Identifying Spiral Cable Sub
-Assy Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Tester connectionConditionSpecified value
C13-2 - E2-31 (CCS)AlwaysBelow 1 ohms
C13-4 - E3-20 (CCHG)AlwaysBelow 1 ohms
C13-2 - Body groundAlways10 kohms or higher
C13-4 - Body groundAlways10 kohms or higher