Identifying condition LEXUS LS430 2003 Factory Repair Manual

Fig. 82: Disconnecting ECM Connector Terminals
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NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go To Next Step.
5.CHECK HARNESS AND CONNECTOR (SPIRAL CABLE SUB-ASSY - BODY GROUND)
a. Measure the resistance according to the value(s) in the table below.
Standard:
SPIRAL CABLE SUB-ASSY CONNECTOR TERMINALS RESISTANCE
SPECIFICATION
Fig. 83: Identifying Spiral Cable Sub
-Assy Connectors
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Tester connectionConditionSpecified value
C13-3 - Body groundAlwaysBelow 1 ohms

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HINT:
When a particular warning light stays blinking, a ground short in the wiring of terminal TC of the DLC3 or an
internal ground short in the relevant ECU is suspected.
INSPECTION PROCEDURE
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.
Standard:
ECM CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Fig. 85: Identifying DLC3 Connector (TC) Terminals

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Tester connectionConditionSpecified condition
TC (E2-3) - TC (D1 - 13)AlwaysBelow 1 ohms

Fig. 86: Disconnecting E2 Connector From ECM
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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.
Standard:
ECM CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Fig. 87: Identifying DLC3 Connector (CG) Terminals

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NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (DLC3 - BODY GROUND)
Tester connectionConditionSpecified condition
CG (D1-4) - Body groundAlwaysBelow 1 ohms

OK: Go To Next Step.
3.CHECK HARNESS AND CONNECTOR (TC of DLC3 - BODY GROUND)
a. Measure the resistance according to the value(s) in the table below.
Standard:
ECM CONNECTOR TERMINALS RESISTANCE SPECIFICATION
Fig. 88: Identifying DLC3 Connector (TC) Terminals

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NG: REPAIR OR REPLACE WIRE HARNESS AND EACH ECU
OK: REPLACE ECM (SEE REPLACEMENT
)
Tester connectionConditionSpecified condition
TC (D1-13) - Body groundAlways10 kohms or higher

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. 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. 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

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

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

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Fig. 37: Fail
-Safe Chart
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3.Only in the vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic radar cruise control is in operation, the system
maintains the stored vehicle speed in the ECM and cancels the d
ynamic radar cruise control operation.

Fig. 38: Identifying CRUISE Main Indicator Light And Master Warning Light
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Fig. 39: Fail
-Safe Chart (1 Of 2)
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4.Constant speed control mode and vehicle-to-vehicle distance control mode:
If the following conditions are detected while the dynamic radar cruise control is in operation, the system
clears the stored vehicle speed and cancels the dynamic radar 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)
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