LEXUS LS430 2003 Factory Repair Manual

Fig. 30: Identifying DLC3 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
DLC3 CONNECTOR TERMINALS RESISTANCE
HINT:
If the displa
y shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the hand-held
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

tester to the DLC3, turned the ignition switch to the ON position and operated the tester, there is a
problem on either the vehicle side or the tool side.
If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the
original vehicle.
If communication is still impossible when the tool is connected to another vehicle, the problem is
probably in the tool itself, so consult the Service Department listed in the tool's instruction manual.
4.CHECK THE INDICATOR
a. Turn the ignition switch to the ON position.
b. Check that the CRUISE main indicator light and RADAR READY indicator come on when the
main switch ON-OFF button is pushed on, and that the indicator light goes off when the ON-OFF
button is pushed off.
HINT:
If the indicator check result shows a problem, proceed to troubleshooting (see CRUISE MAIN
INDICATOR LIGHT CIRCUIT ) for the combination meter section.
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51004700030035002400270024003500030035002800240027[Y Indicator

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:

If a malfunction occurs in the vehicle speed sensors, the stop lamp switch, or other related parts during
cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and blinks the CRUISE
main indicator light. This indicator light informs the driver of the malfunction. At the same time, the
malfunction is stored as a diagnostic trouble code.
Fig. 32: Identifying Blinking Pattern Of CRUISE Main Indicator Light

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1.DTC CHECK
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. Read the DTCs by following the prompts on the tester screen.
2.DTC CLEAR
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position.
c. Clear the DTCs following the prompts on the tester screen.
HINT:
Refer to the han
d-held tester operators manual for further details.

Fig. 33: Connecting Hand-Held Tester To DLC3
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.Constant speed control mode and vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic laser cruise control is in operation, the system
clears the stored vehicle speed in the ECM and cancels the dynamic laser cruise control operation.
Fig. 34: Identifying CRUISE Main Indicator Light And Master Warning Light

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Fig. 35: Fail
-Safe Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
2.Only in the vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic laser cruise control is in operation, the system
clears the stored vehicle speed in the ECM and cancels the dynamic laser cruise control operation.
Fig. 36: Identifying CRUISE Main Indicator Light And Master Warning Light

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Fig. 37: Fail
-Safe Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
3.Only in the vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic laser cruise control is in operation, the system
maintains the stored vehicle speed in the ECM and cancels the d
ynamic laser cruise control operation.

Fig. 38: Identifying Master Warning Light
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Fig. 39: Fail
-Safe Chart (1 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
4.Constant speed control mode and vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic laser cruise control is in operation, the system
clears the stored vehicle speed and cancels the dynamic laser cruise control operation.
HINT:
In the vehicle-to-vehicle distance control mode, the stored vehicle speed in the ECM is maintained.
Fig. 40: Fail
-Safe Chart (2 Of 2)

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
1.DATA LIST
HINT:
From the DATA LIST displayed on the hand-held tester, the value of components such as the switch,
sensor, and actuator can be read without parts removal. Reading the DATA LIST as the first step of
troubleshooting is one way to shorten labor time.
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".
CC (ECM):
DATA LIST (CC (ECM))
Item
Measurement Item /
Display (Range)
Normal ConditionDiagnostic Note
ACCEL REQUESTAccelerator request signal /
min.: -2621.44 k/h/s, max.:
2621.36 k/h/sNo vehicle in front-
VEHICLE
DISTANCELaser sensor / min.: 0 m (0ft),
max.: 255m (836.65 ft)Distance to the vehicle in front-
L/C OPTION FLAGLaser cruise option flag / NO,
YESYES: Vehicle to vehicle distance
mode-
DISTANCE TIMECar distance time setting
condition /SHRT, MID,
LONG, NOThe vehicle selected by distance
control switch-
O/D CUT RQSTO/D cut request / NOT REQ,
REQUESTNOT REQ: Idling-
3RD SHIFT DOWNShift down request to 3rd
gear / NOT REQ, REQUESTNOT REQ: Idling-
4TH SHIFT DOWNShift down request to 4th
gear / NOT REQ, REQUESTNOT REQ: Idling-
ALARM RQSTAlarm request signal / NOT
REQ, REQUESTREQUEST: When beeping NOT
REQ: When not beeping-
THROTTLE CLOSEAll throttle close request /
NOT REQ, REQUESTON: REQUEST OFF: NOT
REQUEST-
BRAKE CTRL RQSTBrake control request / NOT
REQ, REQUESTON: REQUEST OFF: NOT
REQUEST-
TARG DECL SLOPECruise target deceleration
slope / 0.03, 0.06, 0.11, 0.160.03, 0.06, 0.11, 0.16-

VEHICLE SPDVehicle speed sensor/min.: 0
km/h (0 mph), max.: 255
km/h (158 mph)Actual vehicle speed-
MEMORY SPDCruise control memorized
speed / min.: 0 km/h (0 mph),
max.: 255 km/h (158 mph)Memorized speed: Cruise control
activated-
THROTTLERequired throttle opening
angle / min.: 0 deg, max.: 125
degRequired throttle opening angle:
Cruise control activated-
RQST TORQUECruise request torque/min.: -
1024 Nm, max.: 1016 Nm--
CRUISE CTRLCruise control system active
condition / ON or OFFON: Cruise control activated
OFF: Cruise control inactivated-
MAIN SW (MAIN)Main SW signal (Main
CPU) / ON or OFFON: Main SW ON (Pushed on)
OFF: Main SW OFF (Pushed
off)*3
MAIN SW (SUB)Main SW signal (Sub CPU) /
ON or OFFON: Main SW ON (Pushed on)
OFF: Main SW OFF (Pushed
off)*3
CCS READY MCruise control system
standby condition (Main
CPU) / ON or OFFON <=> OFF: Change ON/OFF
each time Main SW is pushed.*1
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic Note
CCS READY SCruise control system
standby condition (Sub
CPU) / ON or OFFON <=> OFF: Change ON/OFF
each time Main SW is pushed.*1
CCS INDICATOR MCruise indicator signal (Main
CPU) / ON or OFFON: "CCS READY" ON OFF:
"CCS READY" OFF*2
CCS INDICATOR SCruise indicator signal (Sub
CPU) / ON or OFFON: "CCS READY" ON OFF:
"CCS READY" OFF*2
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-
STP LIGHT SW MStop lamp SW signal (Main
CPU) / ON or OFFON: Brake pedal depressed OFF:
Brake pedal released-
STP LIGHT SW S1Stop lamp SW signal (Sub
CPU) / ON or OFFON: Brake pedal depressed OFF:
Brake pedal released-
STP LIGHT SW S2Stop lamp SW signal (Sub
CPU) / ON or OFFON: Brake pedal depressed OFF:
Brake pedal released-
SHIFT D POSPNP SW signal (D position) /
ON or OFFON: Shift D position OFF:
Except shift D position-

HINT:
*3 is OK, but *1 is NG --> ECM failure
*1 is OK, but *2 is NG --> DTC output or ECM failure
*3 is OK, but CRUISE main indicator light does not come on --> Indicator, W/H, or ECM failure
MULTI-INFORMATION DISPLAY CONTROL SWITCH (STEERING PAD SWITCH
MODULATOR):
DATA LIST (MULTI-INFORMATION DISPLAY CONTROL SWITCH (STEERING PAD
SWITCH MODULATOR))
2.ACTIVE TEST
HINT:
Performing the ACTIVE TEST using the hand-held tester allows components such as the relay, VSV, and
actuator to operate without parts removal. Performing the ACTIVE TEST as the first step of
troubleshooting is one way to shorten labor time.
It is possible to display the DATA LIST during the ACTIVE TEST.
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, perform the "ACTIVE TEST".
HINT:
The ignition switch must be turned to the ON position to proceed to the ACTIVE TEST using the hand-
held tester.
COMBINATION METER ASSY:
ACTIVE TEST DETAIL (COMBINATION METER ASSY)
VSC FAIL SAFEVSC fail-safe flag/ON or
OFF--
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic
Note
MULTI
DSP2 SWSteering pad switch (DISP2)
signal / ON or OFFON <=> OFF: Change ON/OFF each time
steering pad switch (DISP2) SW is pushed.-
ItemVehicle Condition / Test DetailsDiagnostic Note
CRUISE INDIC"CRUISE" indicator is ON / OFF-

HINT:
If a trouble code is displayed during the DTC check, check the circuit listed for that code. For details of each
code, refer to the DTC chart below.
DIAGNOSTIC TROUBLE CODE CHART
L-CRUISE DISPGraphic area is ON / OFF((1))
L-CRS CHECK IND"CHECK CRUISE SYSTEM" indicator is ON / OFF-
L-CRS READY IND"RADAR READY" indicator is ON / OFF-
(1)The entire graphic area in the combination meter will light up.
DTCDescription
DTC P0500, DTC
P0503
VEHICLE SPEED SENSOR CIRCUIT MALFUNCTION
DTC P0571STOP LIGHT SWITCH CIRCUIT MALFUNCTION
DTC P0607INPUT SIGNAL CIRCUIT MALFUNCTION
DTC P1615, DTC
U1101
COMMUNICATION ERROR FROM DISTANCE CONTROL ECU TO
ECM
DTC P1616, DTC
U0100
COMMUNICATION ERROR FROM ECM TO DISTANCE CONTROL
ECU
DTC P1617DISTANCE CONTROL ECU MALFUNCTION
DTC P1630, DTC
U0122
COMMUNICATION ERROR FROM VSC TO ECM
DTC P1631, DTC
U0100
COMMUNICATION ERROR FROM ECM TO VSC
DTC P1575WARNING BUZZER MALFUNCTION
DTC P1578BRAKE SYSTEM MALFUNCTION
DTC U0235LOST COMMUNICATION WITH CRUISE CONTROL FRONT
DISTANCE RANGE SENSOR
DTC U1102LOST COMMUNICATION WITH RADAR SENSOR
DTC P1570RADAR SENSOR MALFUNCTION
DTC P1572IMPROPER AIMING OF RADAR SENSOR BEAM AXIS
DTC U0126LOST COMMUNICATION WITH STEERING ANGLE SENSOR MODULE
DTC U0123LOST COMMUNICATION WITH YAW RATE SENSOR MODULE