CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short in CAN Bus Lines; 2006 MY LX470 [05/2005

Last Modified: 4-30-2014	6.6 J	Doc ID: RM000000WIN005X
Model Year: 2006	Model: LX470	Prod Date Range: [05/2005 - ]
Title: CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Short in CAN Bus Lines; 2006 MY LX470 [05/2005 - ]

Short in CAN Bus Lines

DESCRIPTION

There may be a short circuit between the CAN bus line when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is below 54 Ω.

Symptom	Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of DLC3 is below 54 Ω.	Short between CAN bus lines ECM Gateway ECU Translate ECU Junction connector

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (DLC3 SUB BUS LINE)

(a) Disconnect the J34 DLC3 sub bus line connector from the junction connector B side.

NOTICE:

Before disconnecting the connector, make a note of where it is connected.

Reconnect the connector to its original position.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	1 MΩ or higher

REPAIR OR REPLACE DLC3 SUB BUS LINE AND CONNECTOR

2.	CONNECT CONNECTOR

(a) Reconnect the J34 DLC3 sub bus line connector to the junction connector B side.

3.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (ECM MAIN BUS LINE)

(a) Disconnect the J31 ECM main bus line connector from the junction connector B side.

NOTICE:

Before disconnecting the connector, make a note of where it is connected.

Reconnect the connector to its original position.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	108 to 132 Ω

GO TO STEP 8

4.	CONNECT CONNECTOR

(a) Reconnect the J31 ECM main bus line connector to the junction connector B side.

5.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (GATEWAY ECU MAIN BUS LINE)

(a) Disconnect the J32 gateway ECU main bus line connector from the junction connector B side.

NOTICE:

Before disconnecting the connector, make a note of where it is connected.

Reconnect the connector to its original position.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	108 to 132 Ω

GO TO STEP 10

6.	CONNECT CONNECTOR

(a) Reconnect the J32 gateway ECU main bus line connector to the junction connector B side.

7.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (TRANSLATE ECU SUB BUS LINE)

(a) Disconnect the J33 translate ECU sub bus line connector from the junction connector B side.

NOTICE:

Before disconnecting the connector, make a note of where it is connected.

Reconnect the connector to its original position.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	54 to 67 Ω

GO TO STEP 12

REPLACE JUNCTION CONNECTOR

8.	CONNECT CONNECTOR

(a) Reconnect the J31 ECM main bus line connector to the junction connector B side.

9.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (ECM MAIN BUS LINE)

(a) Disconnect the E9 ECM connector.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	108 to 132 Ω

REPLACE ECM

REPAIR OR REPLACE ECM MAIN BUS LINE AND CONNECTOR (CAN-H, CAN-L)

10.	CONNECT CONNECTOR

(a) Reconnect the J32 gateway ECU main bus line connector to the junction connector B side.

11.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (GATEWAY ECU MAIN BUS LINE)

(a) Disconnect the G5 gateway ECU connector.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	108 to 132 Ω

REPLACE GATEWAY ECU

REPAIR OR REPLACE GATEWAY ECU MAIN BUS LINE AND CONNECTOR (CAN-H, CAN-L)

12.	CONNECT CONNECTOR

(a) Reconnect the J33 translate ECU sub bus line connector to the junction connector B side.

13.	CHECK CAN BUS LINES FOR SHORT CIRCUIT (TRANSLATE ECU SUB BUS LINE)

(a) Disconnect the T39 translate ECU connector.

(b) Measure the resistance of the DLC3.

Standard resistance:

Tester Connection	Condition	Specified Condition
D8-6 (CANH) - D8-14 (CANL)	Ignition switch OFF	54 to 67 Ω

REPLACE TRANSLATE ECU

REPAIR OR REPLACE TRANSLATE ECU SUB BUS LINE AND CONNECTOR (CAN-H, CAN-L)