LEXUS LS430 2003 Factory Repair Manual

Standard:
CAN MAIN BUS LINE CONNECTOR (J45) TERMINALS RESISTANCE
NG: REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN-H, CAN-L)
OK: REPLACE JUNCTION CONNECTOR (P-CAN J/C)
CIRCUIT DESCRIPTION
There may be a short circuit between the CAN bus lines when the resistance between terminals 6 (CANH) and
14 (CANL) of the DLC3 is below 54 ohms.
Fig. 84: Problem Symptom Diagnostic Chart

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WIRING DIAGRAM
Tester connectionConditionSpecified value
J45-1 (CANH) - J45-2 (CANL)Ignition Switch OFF108 to 132 ohms

Fig. 85: Wiring Diagram - CAN Bus Lines For Short Circuit (W/ Lexus Navigation System)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK CAN BUS LINES FOR SHORT CIRCUIT (DLC3 SUB BUS LINE)

Fig. 86: Disconnecting DLC3 Sub Bus Line Connector (J42) From D-CAN J/C B Side (W/O Earth
Terminal)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Turn the ignition switch to the LOCK position.
b. Disconnect the DLC3 sub bus line connector (J42) from the D-CAN J/C B side (w/o earth
terminal).

Fig. 87: Identifying DLC3 Connector terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
c. Measure the resistance according to the value (s) in the table below.
Standard:
DLC3 CONNECTOR TERMINALS RESISTANCE
NG: REPAIR OR REPLACE DLC3 SUB BUS LINE OR CONNECTOR (CAN-H, CANL)
OK: GO TO NEXT STEP
2.CONNECT CONNECTOR
a. Reconnect the DLC3 sub bus line connector (J42) to the D-CAN J/C B side (w/o earth terminal).
3.CHECK CAN BUS LINES FOR SHORT CIRCUIT (CAN BUSES TO D-CAN J/C)
Tester connectionConditionSpecified value
D1-6 (CANH) - D1-14 (CANL)Ignition Switch OFF1 Mohms or more

Fig. 88: Disconnecting CAN Main Bus Line Connector (J45) From P-CAN J/C A Side (W/Earth
Terminal)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Disconnect the CAN main bus line connector (J45) from the P-CAN J/C A side (w/earth terminal).

Fig. 89: Identifying DLC3 Connector terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Measure the resistance according to the value (s) in the table below.
Standard:
DLC3 CONNECTOR TERMINALS RESISTANCE
OK: Go to step 26
NG: GO TO NEXT STEP
4.CONNECT CONNECTOR
a. Reconnect the CAN main bus line connector (J45) to the P-CAN J/C A side (w/earth terminal).
5.CHECK CAN BUS LINES FOR SHORT CIRCUIT (SUSPENSION CONTROL ECU SUB BUS
Tester connectionConditionSpecified value
D1-6 (CANH) - D1-14 (CANL)Ignition Switch OFF108 to 132 ohms

LINE)
Fig. 90: Disconnecting Suspension Control ECU Sub Bus Line Connector (J38) From D
-CAN J/C A
Side (W/Earth Terminal)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Disconnect the suspension control ECU sub bus line connector (J38) from the D-CAN J/C A side
(w/earth terminal).

Fig. 91: Identifying DLC3 Connector terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Measure the resistance according to the value (s) in the table below.
Standard:
DLC3 CONNECTOR TERMINALS RESISTANCE
OK: Go to step 16
NG: GO TO NEXT STEP
Tester connectionConditionSpecified value
D1-6 (CANH) - D1-14 (CANL)Ignition Switch OFF54 to 69 ohms

6.CONNECT CONNECTOR
a. Reconnect the suspension control ECU sub bus line connector (J38) to the D-CAN J/C A side
(w/earth terminal).
7.CHECK CAN BUS LINES FOR SHORT CIRCUIT (GATEWAY ECU)
Fig. 92: Disconnecting Gateway ECU Sub Bus Line Connector (J36) From D
-CAN J/C A Side
(W/Earth Terminal)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
a. Disconnect the gateway ECU sub bus line connector (J36) from the D-CAN J/C A side (w/earth
terminal).

Fig. 93: Identifying DLC3 Connector terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Measure the resistance according to the value (s) in the table below.
Standard:
DLC3 CONNECTOR TERMINALS RESISTANCE
OK: Go to step 18
NG: GO TO NEXT STEP
Tester connectionConditionSpecified value
D1-6 (CANH) - D1-14 (CANL)Ignition Switch OFF54 to 69 ohms