Check Bus 4 Line for Short to GND [06/2018 - 08/2020]: Procedure

1. Disconnect the cable from the negative (-) battery terminal.
2. Disconnect the N99 No. 7 CAN junction connector.
3. 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 Tire Pressure Warning ECU and Receiver
   *c	to Occupant Detection ECU	*d	to Central Gateway ECU (Network Gateway ECU)
   *e	to No. 4 CAN Junction Connector	*f	to Absorber Control ECU (w/ AVS System)

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Connected to
   N99-1 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Tire pressure warning ECU and receiver
   N99-7 (CANL) - G57-4 (CG)
   N99-2 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Occupant detection ECU
   N99-8 (CANL) - G57-4 (CG)
   N99-3 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Central gateway ECU (network gateway ECU)
   N99-9 (CANL) - G57-4 (CG)
   N99-4 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	No. 4 CAN junction connector
   N99-10 (CANL) - G57-4 (CG)
   N99-5 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Absorber control ECU*
   N99-11 (CANL) - G57-4 (CG)

   1. *: w/ AVS System

   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: 

A 

REPLACE NO. 7 CAN JUNCTION CONNECTOR 

Result: 

C 

See step  3

Result: 

D 

See step  6

Result: 

B 

See step  2

1. Disconnect the G66 central gateway ECU (network gateway ECU) connector.
2. 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
   N99-3 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher
   N99-9 (CANL) - G57-4 (CG)

   Result

   Result
   OK
   NG

Result: 

OK 

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU). Refer to  REMOVAL [06/2018 - 08/2021] 

Result: 

NG 

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

1. Disconnect the G99 No. 4 CAN junction connector.
2. 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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G99-6 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher
   G99-17 (CANL) - G57-4 (CG)

   Result

   Result
   OK
   NG

Result: 

NG 

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

Result: 

OK 

See step  4

1. Disconnect the G98 No. 4 CAN junction connector.
2. 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. 2 CAN Junction Connector
   *c	to Steering Sensor	-	-

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Connected to
   G98-6 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	No. 2 CAN junction connector
   G98-17 (CANL) - G57-4 (CG)
   G98-7 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Steering sensor
   G98-18 (CANL) - G57-4 (CG)

   Result

   Result	Proceed to
   OK	A
   NG (Line to No. 2 CAN junction connector)	B
   NG (Line to ECU or sensor)	C

Result: 

A 

REPLACE NO. 4 CAN JUNCTION CONNECTOR 

Result: 

C 

See step  6

Result: 

B 

See step  5

1. Disconnect the A69 No. 2 CAN junction connector.
2. 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. 2 CAN Junction Connector)	*b	to Brake Actuator Assembly
   *c	to Airbag ECU Assembly	*d	to Rack and Pinion Power Steering Gear Assembly
   *e	to No. 4 CAN Junction Connector	-	-

   Standard Resistance

   Tester Connection	Condition	Specified Condition	Connected to
   A69-1 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Brake actuator assembly
   A69-11 (CANL) - G57-4 (CG)
   A69-2 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Airbag ECU assembly
   A69-12 (CANL) - G57-4 (CG)
   A69-4 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	Rack and pinion power steering gear assembly
   A69-14 (CANL) - G57-4 (CG)
   A69-5 (CANH) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher	No. 4 CAN junction connector
   A69-15 (CANL) - G57-4 (CG)

   Result

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

Result: 

A 

REPLACE NO. 2 CAN JUNCTION CONNECTOR 

Result: 

B 

REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 4 CAN JUNCTION CONNECTOR) 

Result: 

C 

See step  6

1. Reconnect all wire harness connectors.
2. 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 [06/2018 - 07/2019] , or refer to TERMINALS OF ECU [07/2019 - 10/2019] , or refer to TERMINALS OF ECU [10/2019 - 08/2020]

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

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   G66-22 (CA2H) - G57-4 (CG)	Cable disconnected from negative (-) battery terminal	200 Ω or higher
   G66-7 (CA2L) - G57-4 (CG)

   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

   Result
   OK
   NG

Result: 

OK 

REPLACE ECU OR SENSOR 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR