2003 LEXUS LS430 ignition

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

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

This DTC indicates the internal abnormalities of the ECM.
DTC P0607 PROBLEM SYMPTOM DIAGNOSTIC
HINT:
The ECM receives signals from each sensor to control all the functions of the cruise control with the
microcomputer.
When a trouble code is detected, fail-safe remains on until the ignition switch is turned off.
INSPECTION PROCEDURE
1.REPLACE ECM (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The cruise control main switch operates seven functions: SET, COAST, TAP-DOWN, RESUME, ACCEL,
TAP-UP, and CANCEL. The SET, TAP-DOWN and COAST functions, and the RESUME, TAP-UP and
ACCEL functions are operated with the same switch respectively. The cruise control main switch is an
automatic return type switch which turns on only while operating it in each arrow direction and turns off after
releasing it. The internal contact point of the cruise control main switch is turned on with the switch operation.
Then the ECM reads the resistance value that has been changed by the switch operation to control SET,
COAST, RESUME, ACCEL and CANCEL.
WIRING DIAGRAM
DTC No.Detection ItemTrouble Area
P0607The ECM has a supervisory CPU and a control ECU inside. When
each input STP signal is different for 0.15 sec. or more, this trouble
code is output. This trouble code is output after 0.4 sec. has passed
from the time the cruise cancel input signal (STP input) is input into
the ECM.ECM

Fig. 26: Wiring Diagram - Cruise Control Switch Circuit
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE ON HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. Accordin
g to the display on the tester, read the "DATA LIST".

Fig. 31: [Disconnecting ECM Connector]
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE ECM (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The ECM detects a cruise control switch signal and sends it to the combination meter via CAN and
BEAN. Then the CRUISE main indicator light comes on.
The CRUISE main indicator light circuit uses CAN and BEAN for communication. If there are any
malfunctions in this circuit, check for DTCs in the CAN communication system and multiplex
communication system.
INSPECTION PROCEDURE
1.PERFORM ACTIVE TEST BY HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Check the CRUISE main indicator light by using ACTIVE TEST.
ACTIVE TEST DETAIL (COMBINATION METER ASSY)
OK: Indicator light comes on/goes off.
NG: GO TO COMBINATION METER SYSTEM (SEE HOW TO PROCEED WITH
TROUBLESHOOTING )
OK: Go to next step
2.READ VALUE ON HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position and turn the hand-held tester main switch on.
c. Select the item below in the "DATA LIST", and read the display on the hand-held tester.
DATA LIST (CC (ECM))
ItemVehicle Condition / Test DetailsDiagnostic Note
CRUISE INDIC"CRUISE" indicator is ON / OFF-
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic
Note
CCS INDICATOR
MCruise indicator signal (Main
CPU) /ON or OFFON: "CCS READY" ON OFF:
"CCS READY" OFF-

Fig. 1: Removing Cruise Control ECU Assy
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
8.INSTALL CRUISE CONTROL ECU ASSY
a. Install the cruise control ECU (distance control ECU) assy with the nut.
Torque: 5.5 N.m (56 kgf.cm, 49 in.lbf)
9.INITIALIZE DISTANCE CONTROL ECU
a. Be sure to perform the following procedures after replacing the distance control ECU.
1. Turn the ignition switch to the ON position.
2. Push the cruise main switch ON-OFF button on.

c. Adjust the laser beam axis
1. Turn the ignition switch to the ON position.
2. Push the cruise control main switch ON-OFF button on.
3. Connect the hand-held tester to the DLC3, and turn the power ON.
Fig. 9: Connecting Hand
-Held Tester To DLC3
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
4. Operate by following the screen menu and select "BEAM AXIS ADJUST" of the Laser Cruise
Control, then press the "ENTER" key.
HINT:
Pressing the "ENTER" key will make the ECM transfer to BEAM AXIS ADJUSTMENT
MODE.
When the ECM transfers to BEAM AXIS ADJUSTMENT MODE, the buzzer sounds for 1
second.

Fig. 27: Measuring To Left And Placing Reflector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
f. Adjust the radar beam axis
1. Turn the ignition switch to the ON position.
2. Push the cruise control main switch ON-OFF button on.
3. Connect the hand-held tester to the DLC3, and turn the power ON.
Fig. 28: Connecting Hand
-Held Tester To DLC3
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
4. Operate by following the screen menu and select "BEAM AXIS ADJUST" of the Radar
Cruise Control, then press the "ENTER" key.
HINT:
Pressing the "ENTER" key will make the ECM transfer to BEAM AXIS
ADJUSTMENT MODE.
When the ECM transfers to BEAM AXIS ADJUSTMENT MODE, the buzzer sounds
for 1 second.