Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

DESCRIPTION

There may be a short circuit between the CAN main bus lines and/or CAN branch lines when the resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network gateway ECU) is below 54 Ω.

Detection Item

Trouble Area

Resistance between terminals 18 (CA4H) and 17 (CA4L) of central gateway ECU (network gateway ECU) is below 54 Ω.

  • Short in CAN main lines
  • Short in CAN branch lines
  • Central gateway ECU (network gateway ECU)
  • ECM
  • Main body ECU (multiplex network body ECU)
  • Air conditioning amplifier assembly
  • Airbag sensor assembly
  • Spiral cable with sensor sub-assembly
  • Combination meter assembly
  • Certification ECU (smart key ECU assembly)*1
  • 4 wheel drive control ECU*2
  • Door control and tire pressure monitoring system receiver assembly*3
  • Brake booster assembly (skid control ECU)*4
  • Brake actuator assembly (skid control ECU)*5
  • No. 1 CAN junction connector
  • No. 2 CAN junction connector
  • *1: w/ Smart Key System
  • *2: for 4WD
  • *3: w/ Tire Pressure Warning System and Tire Inflation Pressure Display Function
  • *4: for Hydraulic Brake Booster
  • *5: for Vacuum Brake Booster

WIRING DIAGRAM CAUTION / NOTICE / HINT

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

  • 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

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

    Click here

  • 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

  • If the main body ECU (multiplex network body ECU) or certification ECU (smart key ECU assembly) is replaced, refer to Registration.

    Click here

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 IN CAN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR)

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

(b) Disconnect the No. 1 CAN junction connector.

Text in Illustration

*a

Front view of wire harness connector

(to No. 1 CAN Junction Connector)

*b

to Brake Booster Assembly (Skid Control ECU) (for Hydraulic Brake Booster) or Brake Actuator Assembly (Skid Control ECU) (for Vacuum Brake Booster)

*c

to No. 2 CAN Junction Connector

*d

to Air Conditioning Amplifier Assembly

*e

to ECM

*f

to Central Gateway ECU (Network Gateway ECU)

*g

to Airbag Sensor Assembly

*h

to 4 Wheel Drive Control ECU (for 4WD)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connected to

J16-1 (CANH) - J16-11 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Brake booster assembly (skid control ECU)*1 or brake actuator assembly (skid control ECU)*2

J16-2 (CANH) - J16-12 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

No. 2 CAN junction connector

J16-3 (CANH) - J16-13 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Air conditioning amplifier assembly

J16-5 (CANH) - J16-15 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

ECM

J16-6 (CANH) - J16-16 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Central gateway ECU (network gateway ECU)

J16-7 (CANH) - J16-17 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Airbag sensor assembly

J16-8 (CANH) - J16-18 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

4 wheel drive control ECU*3

  • *1: for Hydraulic Brake Booster
  • *2: for Vacuum Brake Booster
  • *3: for 4WD
Result

Result

Proceed to

OK

A

NG (ECM CAN main line)

B

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

C

NG (No. 2 CAN junction connector CAN main line)

D

NG (ECU or sensor CAN branch lines)

E

A

REPLACE NO. 1 CAN JUNCTION CONNECTOR

B

REPAIR OR REPLACE CAN MAIN LINE OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR - ECM)

D

GO TO STEP 3

E

GO TO STEP 4

C

2.

CHECK FOR SHORT IN CAN BUS LINES (NO. 1 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

(a) Disconnect the N36 central gateway ECU (network gateway ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

J16-6 (CANH) - J16-16 (CANL)

Cable disconnected from negative (-) battery terminal

1 MΩ or higher

Text in Illustration

*a

Front view of wire harness connector

(to No. 1 CAN Junction Connector)

*b

to Central Gateway ECU (Network Gateway ECU)

OK

REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

NG

REPAIR OR REPLACE CAN BRANCH LINE OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))

3.

CHECK FOR SHORT IN CAN BUS LINES (NO. 2 CAN JUNCTION CONNECTOR)

(a) Reconnect the J16 No. 1 CAN Junction Connector.

(b) Disconnect the No. 2 CAN junction connector.

Text in Illustration

*a

Front view of wire harness connector

(to No. 2 CAN Junction Connector)

*b

to No. 1 CAN Junction Connector

*c

to Door Control and Tire Pressure Monitoring System Receiver Assembly (w/ Tire Pressure Warning System and Tire Inflation Pressure Display Function)

*d

to Main Body ECU (Multiplex Network Body ECU)

*e

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

*f

to Combination Meter Assembly

*g

to Spiral Cable with Sensor Sub-assembly

-

-

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Connected to

J3-1 (CANH) - J3-11 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

No. 1 CAN junction connector

J3-2 (CANH) - J3-12 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Door control and tire pressure monitoring system receiver assembly*1

J3-4 (CANH) - J3-14 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Main body ECU (multiplex network body ECU)

J3-5 (CANH) - J3-15 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Certification ECU (smart key ECU assembly)*2

J3-6 (CANH) - J3-16 (CANL)

Cable disconnected from negative (-) battery terminal

108 to 132 Ω

Combination meter assembly

J3-7 (CANH) - J3-17 (CANL)

Cable disconnected from negative (-) battery terminal

200 Ω or higher

Spiral cable with sensor sub-assembly

  • *1: w/ Tire Pressure Warning System and Tire Inflation Pressure Display Function
  • *2: w/ Smart Key System
Result

Result

Proceed to

OK

A

NG (Combination meter assembly CAN main line)

B

NG (No. 1 CAN junction connector CAN main line)

C

NG (ECU or sensor CAN branch lines)

D

A

REPLACE NO. 2 CAN JUNCTION CONNECTOR

B

REPAIR OR REPLACE CAN MAIN LINE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)

C

REPAIR OR REPLACE CAN MAIN LINE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 1 CAN JUNCTION CONNECTOR)

D

4.

CHECK FOR SHORT IN CAN BUS LINES (ECU, SENSOR)

(a) Reconnect the CAN junction connector.

(b) Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the short circuited CAN branch line is connected.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

N36-18 (CA4H) - N36-17 (CA4L)

Cable disconnected from negative (-) battery terminal

54 to 69 Ω

Text in Illustration

*a

Component with harness connected

(Central Gateway ECU (Network Gateway ECU))

HINT:

If the resistance becomes normal (between 54 and 69 Ω) when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.

OK

REPLACE ECU OR SENSOR

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

Open in Bus 3 Main Bus Line
DESCRIPTION There may be an open circuit in one of the CAN main bus lines when the resistance between terminals 6 (CA3H) and 21 (CA3L) of the central gateway ECU (network gateway ECU) is 70 Ω or ...
Other materials:

Oil Level Sensor
Components COMPONENTS ILLUSTRATION ILLUSTRATION Inspection INSPECTION PROCEDURE 1.

Related news

  • Toyota Tacoma 2015-2018 Service Manual: Clutch Master Cylinder
  • Chevrolet Sonic Owners Manual: Steering
  • Mercedes-Benz E-Class: Problems with your vehicle
  • Buick LaCrosse: Exterior Lighting
  • Subaru Legacy: Windows

  • Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit

    Toyota Tacoma 2015-2018 Service Manual: Check Bus 2 Lines for Short Circuit