2003 LEXUS LS430 ignition

NG-A: CHECK CAN MAIN BUS LINE FOR DISCONNECTION (W/O LEXUS NAVIGATION
SYSTEM)
NG-B: CHECK CAN MAIN BUS LINE FOR DISCONNECTION (W/ LEXUS NAVIGATION
SYSTEM)
NG-C: CHECK CAN BUS LINES FOR SHORT CIRCUIT (W/O LEXUS NAVIGATION
SYSTEM)
NG-D: CHECK CAN BUS LINES FOR SHORT CIRCUIT (W/ LEXUS NAVIGATION SYSTEM)
OK: GO TO NEXT STEP
2.CHECK CAN BUS LINE FOR SHORT TO +B
Fig. 34: Identifying DLC3 Connector terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
D1-6 (CANH) - D1-14
(CANL)Ignition Switch
OFF54 ohms or less (w/ LEXUS Navigation
System)NG-D

a. Measure the resistance according to the value (s) in the table below.
Standard:
ECM CONNECTOR TERMINALS RESISTANCE
HINT:
NG-A: w/o LEXUS Navigation System.
NG-B: w/ LEXUS Navigation System.
NG-A: CHECK CAN BUS LINE FOR SHORT TO +B (W/O LEXUS NAVIGATION SYSTEM)

NG-B: CHECK CAN BUS LINE FOR SHORT TO +B (W/ LEXUS NAVIGATION SYSTEM)

OK: GO TO NEXT STEP
3.CHECK CAN BUS LINE FOR SHORT TO GND
Tester ConnectionConditionSpecified value
D1-6 (CANH) - D1-16 (BAT)Ignition Switch OFF1 Mohms or more
D1-14 (CANL) - D1-16 (BAT)Ignition Switch OFF1 Mohms or more

Fig. 35: Identifying DLC3 Connector terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Measure the resistance according to the value (s) in the table below.
Standard:
ECM CONNECTOR TERMINALS RESISTANCE
HINT:
NG-A: w/o LEXUS Navigation System.
NG-B: w/ LEXUS Navigation System.
NG-A: CHECK CAN BUS LINE FOR SHORT TO GND (W/O LEXUS NAVIGATION SYSTEM)
Tester ConnectionConditionSpecified value
D1-4 (CG) - D1-6 (CANH)Ignition Switch OFF1 kohms or more
D1-4 (CG) - D1-14 (CANL)Ignition Switch OFF1 kohms or more

Fig. 38: Check Can Bus Line For Disconnection
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Turn the ignition switch to the LOCK position.
b. Disconnect the skid control ECU connector (S42).
c. Measure the resistance according to the value (s) in the table below.
Standard:
SKID CONTROL ECU CONNECTOR TERMINALS RESISTANCE
NG: REPAIR OR REPLACE SKID CONTROL ECU SUB BUS LINE OR CONNECTOR (CAN-
H, CAN-L)
OK: GO TO NEXT STEP
2.CHECK WIRE HARNESS (IG, GND1, GND2)
Tester ConnectionConditionSpecified value
S42-11 (GANH) - S42-25 (CANL)Ignition Switch OFF54 to 69 ohms

Fig. 39: Identifying Skid Control ECU Connectors
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Measure the resistance according to the value (s) in the table below.
b. Measure the voltage according to the value (s) in the table below.
Standard:
SKID CONTROL ECU CONNECTOR TERMINALS VOLTAGE
NG: REPAIR OR REPLACE WIRE HARNESS OR CONNECTOR
OK: REPLACE SKID CONTROL ECU WITH ACTUATOR (SEE REPLACEMENT
)
Tester ConnectionConditionSpecified value
S42-1 (GND2) - Body groundAlwaysBelow 1
S42-32 (GND1) - Body groundAlwaysBelow 1
S42-46 (IG1) - Body groundIgnition Switch ON10 to 14 V

a. Turn the ignition switch to the LOCK position.
b. Disconnect the steering sensor connector (S16).
c. Measure the resistance according to the value (s) in the table below.
Standard:
STEERING SENSOR CONNECTOR TERMINALS RESISTANCE
NG: REPAIR OR REPLACE STEERING SENSOR SUB BUS LINE OR CONNECTOR (CAN-H,
CAN -L)
OK: GO TO NEXT STEP
2.CHECK WIRE HARNESS (IG1, ESS)
Tester ConnectionConditionSpecified value
S16-10 (CANH) -S16-9 (CANL)Ignition Switch OFF54 to 69 ohms

Fig. 43: Disconnecting Steering Sensor Connector (S16)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Measure the resistance according to the value (s) in the table below.
b. Measure the voltage according to the value (s) in the table below.
Standard:
STEERING SENSOR CONNECTOR TERMINALS RESISTANCE AND VOLTAGE
Tester ConnectionConditionSpecified condition
S16-2 (ESS) - Body groundAlwaysBelow 1 ohms
S16-1 (IG1) - Body groundIgnition Switch ON10 to 14 V

Fig. 46: Identifying Yaw Rate Sensor Connector
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Turn the ignition switch to the LOCK position.
b. Disconnect the yaw rate sensor connector (Y1).
c. Measure the resistance according to the value (s) in the table below.
Standard:
YAW RATE SENSOR CONNECTOR TERMINALS RESISTANCE
NG: REPAIR OR REPLACE YAW RATE SENSOR SUB BUS LINE OR CONNECTOR (CAN-H,
CAN-L)
OK: GO TO NEXT STEP
2.CHECK WIRE HARNESS (IG, GND)
Tester connectionConditionSpecified value
Y1-2 (CANL) - Y1-3 (CANH)Ignition Switch OFF54 to 69 ohms