Check Bus 4 Line for Short to GND [07/2022 - ]: Procedure

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CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 7 CAN JUNCTION CONNECTOR)

Disconnect the cable from the negative (-) auxiliary battery terminal.
Disconnect the No. 7 CAN junction connector.

Measure the resistance according to the value(s) in the table below.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	DLC3	-	-
*a	Front view of wire harness connector (to No. 7 CAN Junction Connector)	*b	to No. 4 CAN Junction Connector
*c	to Central Gateway ECU (Network Gateway ECU)	*d	to Hybrid Vehicle Control ECU
*e	to Tire Pressure ECU and Receiver	*f	to ECM
*g	to Occupant Detection ECU	*h	to Brake Booster with Master Cylinder Assembly
*i	to Absorber Control ECU (w/ AVS)	*j	to Brake Actuator Assembly

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
F94-1 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 4 CAN junction connector
F94-11 (CANL) - F58-4 (CG)		200 Ω or higher	No. 4 CAN junction connector
F94-2 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Central Gateway ECU (Network Gateway ECU)
F94-12 (CANL) - F58-4 (CG)		200 Ω or higher	Central Gateway ECU (Network Gateway ECU)
F94-3 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Hybrid Vehicle Control ECU
F94-13 (CANL) - F58-4 (CG)		200 Ω or higher	Hybrid Vehicle Control ECU
F94-4 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Tire Pressure ECU and Receiver
F94-14 (CANL) - F58-4 (CG)		200 Ω or higher	Tire Pressure ECU and Receiver
F94-5 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	ECM
F94-15 (CANL) - F58-4 (CG)		200 Ω or higher	ECM
F94-6 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Occupant Detection ECU
F94-16 (CANL) - F58-4 (CG)		200 Ω or higher	Occupant Detection ECU
F94-7 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Brake Booster with Master Cylinder Assembly
F94-17 (CANL) - F58-4 (CG)		200 Ω or higher	Brake Booster with Master Cylinder Assembly
F94-8 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Absorber Control ECU*1
F94-18 (CANL) - F58-4 (CG)		200 Ω or higher	Absorber Control ECU*1
F94-9 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Brake Actuator Assembly
F94-19 (CANL) - F58-4 (CG)		200 Ω or higher	Brake Actuator Assembly

*1: w/ AVS

Result

Result	Proceed to
OK	A
NG (Line to central gateway ECU (network gateway ECU))	B
NG (Line to No. 4 CAN junction connector)	C
NG (Line to ECU or sensor)	D

Result:

REPLACE NO. 7 CAN JUNCTION CONNECTOR

Result:

See step 3

Result:

See step 4

Result:

See step 2

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 7 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

Disconnect the F61 central gateway ECU (network gateway ECU) connector.

Measure the resistance according to the value(s) in the table below.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	DLC3	-	-
*a	Front view of wire harness connector (to No. 7 CAN Junction Connector)	*b	to Central Gateway ECU (Network Gateway ECU)

Standard Resistance

Tester Connection	Condition	Specified Condition
F94-2 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
F94-12 (CANL) - F58-4 (CG)		200 Ω or higher

Result

Proceed to
OK
NG

Result:

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU). Refer to REMOVAL [07/2022 - ]

Result:

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 4 CAN JUNCTION CONNECTOR)

Disconnect the F89 No. 4 CAN junction connector.

Measure the resistance according to the value(s) in the table below.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*1	DLC3	-	-
*a	Front view of wire harness connector (to No. 4 CAN Junction Connector)	*b	to No. 7 CAN Junction Connector
*c	to Airbag ECU Assembly	*d	to Power Steering ECU with Motor Assembly
*e	to Steering Sensor	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
F89-5 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	No. 7 CAN junction connector
F89-16 (CANL) - F58-4 (CG)		200 Ω or higher	No. 7 CAN junction connector
F89-6 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Airbag ECU Assembly
F89-17 (CANL) - F58-4 (CG)		200 Ω or higher	Airbag ECU Assembly
F89-7 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Power Steering ECU with Motor Assembly
F89-18 (CANL) - F58-4 (CG)		200 Ω or higher	Power Steering ECU with Motor Assembly
F89-8 (CANH) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher	Steering Sensor
F89-19 (CANL) - F58-4 (CG)		200 Ω or higher	Steering Sensor

Result

Result	Proceed to
OK	A
NG (Line to No. 7 CAN junction connector)	B
NG (Line to ECU or sensor)	C

Result:

REPLACE NO. 4 CAN JUNCTION CONNECTOR

Result:

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 7 CAN JUNCTION CONNECTOR)

Result:

See step 4

CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU OR SENSOR)

Reconnect all wire harness connectors.
Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to GND is connected.
Refer to TERMINALS OF ECU [07/2022 - ]

Measure the resistance according to the value(s) in the table below.

*1	DLC3	-	-
*a	Component with harness connected (Central Gateway ECU (Network Gateway ECU))	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition
F61-22 (CA2H) - F58-4 (CG)	Cable disconnected from negative (-) auxiliary battery terminal	200 Ω or higher
F61-7 (CA2L) - F58-4 (CG)		200 Ω or higher

HINT:

If the resistance changes to 200 Ω or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.
If the resistance does not become normal when the connector is disconnected from the ECU or sensor, check for a short to ground in the wire harness and repair or replace the wire harness or connector if necessary.

Result

Proceed to
OK
NG

Result:

REPLACE ECU OR SENSOR

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR