Open in Bus 4 Main Bus Line [11/2017 - 09/2020]: Procedure

CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) BRANCH LINE)

Disconnect the cable from the negative (-) battery terminal.
Disconnect the O142 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

*a	Front view of wire harness connector (to Central Gateway ECU (Network Gateway ECU))

Standard Resistance

Tester Connection	Condition	Specified Condition
O142-22 (CA2H) - O142-7 (CA2L)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω

NOTE:

When the measured value is 133 Ω or higher and a CAN communication system DTC is output, there may be a fault besides disconnection of the central gateway ECU (network gateway ECU) branch line. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area.

Refer to HOW TO PROCEED WITH TROUBLESHOOTING [11/2017 - 10/2018] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2018 - ]

Result

Result
OK
NG

Result:

REPAIR OR REPLACE CAN BRANCH LINES CONNECTED TO CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

Result:

See step 2

CHECK FOR OPEN IN CAN MAIN BUS LINES (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY))

Disconnect the A89 skid control ECU (brake actuator assembly) connector.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

Standard Resistance

Tester Connection	Condition	Specified Condition
A89-36 (CA2H) - A89-37 (CA2L)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω

Result

Result
OK
NG

Result:

REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to REMOVAL [11/2017 - 11/2021]

Result:

See step 3

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 3 CAN JUNCTION TERMINAL)

Reconnect the A89 skid control ECU (brake actuator assembly) connector.
Disconnect the U55 No. 3 CAN junction terminal connector.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to No. 3 CAN Junction Terminal)

Standard Resistance

Tester Connection	Condition	Specified Condition
U55-3 (CANH) - U55-2 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω

Result

Result
OK
NG

Result:

REPLACE NO. 3 CAN JUNCTION TERMINAL

Result:

See step 4

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 11 CAN JUNCTION CONNECTOR)

Reconnect the U55 No. 3 CAN junction terminal connector.
Disconnect the O161 No. 11 CAN junction connector.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Front view of wire harness connector (to No. 11 CAN Junction Connector)	*b	to Skid Control ECU (Brake Actuator Assembly)
*c	to No. 7 CAN Junction Connector	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
O161-1 (CANH) - O161-12 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	Skid control ECU (brake actuator assembly)
O161-4 (CANH) - O161-15 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	No. 7 CAN junction connector

Result

Result	Proceed to
OK	A
NG (Line to skid control ECU (brake actuator assembly))	B
NG (Line to No. 7 CAN junction connector)	C

Result:

REPLACE NO. 11 CAN JUNCTION CONNECTOR

Result:

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 11 CAN JUNCTION CONNECTOR - SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY))

Result:

See step 5

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 7 CAN JUNCTION CONNECTOR)

Reconnect the O161 No. 11 CAN junction connector.
Disconnect the T32 No. 7 CAN junction connector.

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

*a	Front view of wire harness connector (to No. 7 CAN Junction Connector)	*b	to No. 13 CAN Junction Connector
*c	to No. 11 CAN Junction Connector	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
T32-3 (CANH) - T32-14 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	No. 13 CAN junction connector
T32-5 (CANH) - T32-16 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	No. 11 CAN junction connector

Result

Result	Proceed to
OK	A
NG (Line to No. 11 CAN junction connector)	B
NG (Line to No. 13 CAN junction connector)	C

Result:

REPLACE NO. 7 CAN JUNCTION CONNECTOR

Result:

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR - NO. 11 CAN JUNCTION CONNECTOR)

Result:

See step 6

CHECK FOR OPEN IN CAN MAIN BUS LINES (NO. 13 CAN JUNCTION CONNECTOR)

Reconnect the T32 No. 7 CAN junction connector.
Disconnect the U63 No. 13 CAN junction connector.

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

*a	Front view of wire harness connector (to No. 13 CAN Junction Connector)	*b	to No. 7 CAN Junction Connector
*c	to No. 3 CAN Junction Terminal	-	-

Standard Resistance

Tester Connection	Condition	Specified Condition	Connected to
U63-5 (CANH) - U63-16 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	No. 7 CAN junction connector
U63-6 (CANH) - U63-17 (CANL)	Cable disconnected from negative (-) battery terminal	108 to 132 Ω	No. 3 CAN junction terminal

Result

Result	Proceed to
OK	A
NG (Line to No. 7 CAN junction connector)	B
NG (Line to No. 3 CAN junction terminal)	C

Result:

REPLACE NO. 13 CAN JUNCTION CONNECTOR

Result:

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 13 CAN JUNCTION CONNECTOR - NO. 7 CAN JUNCTION CONNECTOR)

Result:

REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 13 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION TERMINAL)