Last Modified: 04-05-2023 6.11:8.1.0 Doc ID: RM1000000018DN8
Model Year Start: 2018 Model: Sienna Prod Date Range: [11/2017 -           ]
Title: NETWORKING: CAN COMMUNICATION SYSTEM: Check Bus 2 Line for Short to GND; 2018 - 2020 MY Sienna [11/2017 -        ]

Check Bus 2 Line for Short to GND

DESCRIPTION

There may be a short circuit between one of the CAN bus wires and GND when no resistance exists between terminal 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 17 (CA4L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Detection Item

Trouble Area

No resistance exists between terminal 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 17 (CA4L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

  • Short to GND in bus 2 CAN main wires
  • Short to GND in bus 2 CAN branch wires
  • ECM
  • 4WD control ECU*1
  • Airbag sensor assembly
  • Air conditioning amplifier assembly
  • Central gateway ECU (network gateway ECU)
  • Main body ECU (multiplex network body ECU)
  • Brake actuator assembly (skid control ECU)
  • Certification ECU (smart key ECU assembly)*2
  • Power management control ECU*2
  • Steering column assembly (power steering ECU)
  • Steering angle sensor (spiral cable with sensor sub-assembly)
  • Combination meter assembly
  • No. 5 junction connector
  • No. 6 junction connector
  • *1: for AWD
  • *2: w/ Smart Key System

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here 2018 - 2020 MY Sienna [11/2017 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.
  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here 2017 - 2020 MY Sienna [08/2016 -        ]; INTRODUCTION: REPAIR INSTRUCTION: PRECAUTION

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here 2018 - 2020 MY Sienna [11/2017 -        ]; INTRODUCTION: REPAIR INSTRUCTION: INITIALIZATION

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here 2018 MY Sienna [11/2017 - 08/2018]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM 2019 - 2020 MY Sienna [08/2018 -        ]; NETWORKING: CAN COMMUNICATION SYSTEM: DIAGNOSIS SYSTEM

  • Before replacing the ECM, power management control ECU, main body ECU (multiplex network body ECU) or certification ECU (smart key ECU assembly), refer to Registration.

    Click here 2017 - 2020 MY Sienna [08/2016 -        ]; THEFT DETERRENT / KEYLESS ENTRY: ENGINE IMMOBILISER SYSTEM(w/ Smart Key System): REGISTRATION

HINT:

  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (COMBINATION METER ASSEMBLY - NO. 5 JUNCTION CONNECTOR)

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

(b) Disconnect the combination meter assembly connector.

*1

DLC3

*a

Front view of wire harness connector

(to Combination Meter Assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D145-17 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D145-16 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

OK

REPLACE COMBINATION METER ASSEMBLY

NG

2.

CONNECT CONNECTOR

(a) Reconnect the D145 combination meter assembly connector.

NEXT

3.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM - NO. 6 JUNCTION CONNECTOR)

(a) Disconnect the ECM connector.

*1

DLC3

*a

Front view of wire harness connector

(to ECM)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

A69-13 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

A69-26 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

OK

REPLACE ECM

NG

4.

CONNECT CONNECTOR

(a) Reconnect the A69 ECM connector.

NEXT

5.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) - NO. 5 JUNCTION CONNECTOR)

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

*1

DLC3

*a

Front view of wire harness connector

(to Central Gateway ECU (Network Gateway ECU))

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D202-18 (CA4H) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D202-17 (CA4L) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

OK

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

NG

6.

CONNECT CONNECTOR

(a) Reconnect the D202 central gateway ECU (network gateway ECU) connector.

NEXT

7.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 5 JUNCTION CONNECTOR)

(a) Disconnect the No. 5 junction connector.

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 5 Junction Connector)

*b

to No. 6 Junction Connector

*c

to Brake Actuator Assembly (Skid Control ECU)

*d

to Certification ECU (Smart Key ECU Assembly) (w/ Smart Key System)

*e

to Power Management Control ECU (w/ Smart Key System)

*f

to Combination Meter Assembly

*g

to Air Conditioning Amplifier Assembly

*h

to Central Gateway ECU (Network Gateway ECU)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connect to

D179-8 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

No. 6 junction connector

D179-19 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-1 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Brake actuator assembly (skid control ECU)

D179-12 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-3 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Certification ECU (smart key ECU assembly)*

D179-14 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-4 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Power management control ECU*

D179-15 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-7 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Combination meter assembly

D179-18 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-2 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Air conditioning amplifier assembly

D179-13 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D179-5 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Central gateway ECU (network gateway ECU)

D179-16 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

  • *: w/ Smart Key System

Result

Result

Proceed to

OK

A

NG (Combination meter assembly CAN main wire)

B

NG (Central gateway ECU (network gateway ECU) CAN branch wire)

C

NG (No. 6 junction connector CAN main wire)

D

NG (ECU or sensor CAN branch wires)

E

A

REPLACE NO. 5 JUNCTION CONNECTOR

B

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 5 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)

C

REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (NO. 5 JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

E

GO TO STEP 10

D

8.

CONNECT CONNECTOR

(a) Reconnect the D179 No. 5 junction connector.

NEXT

9.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 6 JUNCTION CONNECTOR)

(a) Disconnect the No. 6 junction connector.

*1

DLC3

-

-

*a

Front view of wire harness connector

(to No. 6 Junction Connector)

*b

to No. 5 Junction Connector

*c

to Main Body ECU (Multiplex Network Body ECU)

*d

to 4WD ECU Assembly (for AWD)

*e

to Airbag Sensor Assembly

*f

to ECM

*g

to Steering Column Assembly (Power Steering ECU)

*h

to Steering Angle Sensor (Spiral Cable with Sensor Sub-assembly)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connect to

D180-1 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

No. 5 junction connector

D180-12 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-4 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Main body ECU (multiplex network body ECU)

D180-15 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-5 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

4WD ECU assembly*

D180-16 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-9 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Airbag sensor assembly

D180-20 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-7 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

ECM

D180-18 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-3 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Steering column assembly (power steering ECU)

D180-14 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D180-2 (CANH) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Steering angle sensor (spiral cable with sensor sub-assembly)

D180-13 (CANL) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

  • *: for AWD

Result

Result

Proceed to

OK

A

NG (ECM CAN main wire)

B

NG (No. 5 junction connector CAN main wire)

C

NG (ECU or sensor CAN branch wires)

D

A

REPLACE NO. 6 JUNCTION CONNECTOR

B

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 JUNCTION CONNECTOR - ECM)

C

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 JUNCTION CONNECTOR - NO. 5 JUNCTION CONNECTOR)

D

10.

CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECU, SENSOR)

(a) Reconnect the CAN junction connector.

*1

DLC3

*a

Component with harness connected

(Central Gateway ECU (Network Gateway ECU))

(b) Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to GND is connected.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

D202-18 (CA4H) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

D202-17 (CA4L) - D16-4 (CG)

Cable disconnected from negative (-) battery terminal

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.

OK

REPLACE CORRESPONDING ECU OR SENSOR

NG

REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRES OR CONNECTOR