2003 LEXUS LS430 Identifying ac

Fig. 1: Identifying Dynamic Radar Cruise Control System Electrical Components Location (1 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Fig. 2: Identifying Dynamic Radar Cruise Control System Electrical Components Location (2 Of 2)

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Fig. 15: Identifying Cruise Control Main Switch
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2.INSPECT MODE SWITCH
a. Turn the ignition switch to the ON position.
HINT:
Dynamic radar cruise system is in the default mode.
b. After pushing the ON-OFF button on, push the cruise control main switch to MODE for at least 1
second without any other control. Make sure that only "NORM." and nothing else is indicated on
the display.

1.DISTANCE CONTROL ECU
Fig. 20: Identifying ECU Terminals

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ECU TERMINALS VOLTAGE AND RESISTANCE SPECIFICATION
Symbols (Terminals
No.)Wiring
ColorTerminal DescriptionConditionSpecified
Condition
+B - GND (D2-1 - D2-
12)R-B - BRBatteryAlways10 to 14V
CANH (D2 - 8)LGCAN communication
signalCAN
communication
circuit
-
CANL (D2 - 9)LCAN communication
signalCAN
communication
circuit
-
SGND - Body ground
(D2-10 - Body ground)BR - Body
groundGroundAlwaysBelow 1 ohms
GND - Body ground
(D2-12 - Body ground)BR - Body
groundGroundAlwaysBelow 1ohms
IGB - GND (D2-13 -
D2-12)L-0 - BRIgnition switch ON signalIgnition switch OFF
--> ONBelow 1 V --> 10
to 14V
LRDD - GND (D2-22 -
D2-12)P-L - BRMillimeter wave radar
sensor input signalIgnition switch ONPulse generation
(see waveform 1)
LRRD - GND (D2-23 -
D2-12)L-Y - BRMillimeter wave radar
sensor output signalIgnition switch ONPulse generation
(see waveform 2)

Fig. 22: Signal Waveform Graph (Waveform 2)
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2.ECM
Fig. 23: Identifying ECM Connector Terminals

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Fig. 25: Identifying Millimeter Wave Radar Sensor Connector Terminals
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MILLIMETER WAVE RADAR SENSOR CONNECTOR TERMINALS VOLTAGE AND
RESISTANCE SPECIFICATION
a. Reference: waveform 1
HINT:
Terminal: LRDD - SGND
Symbols (Terminal No.)Wiring
ColorTerminal DescriptionConditionSpecified Condition
LGND - Body ground
(M7-1 - Body ground)B-L -Body
groundGround (Distance signal)AlwaysBelow 1 ohms
SGND - Body ground
(M7-2 - Body ground)B-R - Body
groundGroundAlwaysBelow 1 ohms
LRDD - SGND (M7-3 -
M7-2)B-O - B-RMillimeter wave radar
sensor output signalIgnition
switch ONPulse generation (see
waveform 1)
LRRD - SGND (M7-4 -
M7-2)B-Y - B-RMillimeter wave radar
sensor input signalIgnition
switch ONPulse generation (see
waveform 2)
IGB - SGND (M7-5 - M7-
2)B - B-RPower sourceIgnition
switch ON10 to 14V

Fig. 28: Identifying Master Warning Light And CRUISE Main Indicator Light
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Fig. 29: Identifying Blinking Pattern Of CRUISE Main Indicator Light
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2.DESCRIPTION
a. The ECM controls the dynamic radar cruise control system of the vehicle. The data and DTCs
relating to the dynamic radar cruise control system can be read from the DLC3 of the vehicle. If
either DTC or CRUISE OK is not displayed in the multi-information display on the combination
meter when checking for DTCs, there may be a problem with the combination meter or the CAN
communication and multiplex communication system.
Use the hand-held tester to check and solve the problem.
3.CHECK THE DLC3
a. The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of the DLC3
complies with SAE J1962 and matches the ISO 9141-2 format.

Fig. 30: Identifying DLC3 Connector Terminals
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ECM CONNECTOR TERMINALS RESISTANCE SPECIFICATION
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 14V
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