Networking. Can Communication System (For Hatchback Except Separate Type Yaw Rate Sensor) Open In One Side Of Can Branch Line

If 2 or more ECUs and/or sensors do not appear on the Techstream "Bus Check" screen, one side of the CAN branch wire may be open (one side of the CANH [branch wire]/CANL [branch wire] of the ECU and/or sensor is open).

Symptom	Trouble Area
2 or more ECUs and/or sensors do not appear on the Techstream "CAN Bus Check" screen.	Open in side of CAN branch wire Airbag sensor assembly Skid control ECU (brake actuator assembly)1 Main body ECU (multiplex network body ECU) Power steering ECU assembly Steering angle sensor (spiral cable sub-assembly)2 Air conditioning amplifier assembly No. 1 junction connector No. 2 junction connector

*1: w/ ABS
*2: w/ VSC

WIRING DIAGRAM

Yaris. Ncp93, 131.Networking.Can Communication System (For Sedan).Can Communication System (For Hatchback Except Separate Type Yaw Rate Sensor) Open In One Side Of Can Branch Line

INSPECTION PROCEDURE

NOTICE:

Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.
After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors. If doors need to be opened in order to check connectors, open the doors and leave them open.

HINT:

Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
Perform the following inspection for the ECUs (sensors) which are not displayed on the Techstream. If a malfunction cannot be identified, perform the following inspections for the ECUs (sensors) connected to the CAN communication system.
Do not remove the combination meter assembly and ECM, as they are the end parts of the circuit. If removed, CAN communication will not be possible.
The open circuit confirmation of the combination meter assembly, ECM and main wire is performed in the "Check CAN Bus Line" procedure of "How to Proceed with Troubleshooting". This inspection only has procedures for checking for an open circuit on one side of the CAN branch wire.

1.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY))

Disconnect the A70*1 or A71*2 skid control ECU (brake actuator assembly) connector.
*1: w/ VSC
*2: w/o VSC

Select "Communication Bus Check" on the Techstream (YARIS_NCP93 RM000001RSW02LX.html).
Result
Result
Proceed to
"Skid Control (ABS/VSC/TRAC)" not displayed on Techstream.
A
Several ECUs and sensors other than "Skid Control (ABS/VSC/TRAC)" not displayed on Techstream.
B

Result
Result	Proceed to
"Skid Control (ABS/VSC/TRAC)" not displayed on Techstream.	A
Several ECUs and sensors other than "Skid Control (ABS/VSC/TRAC)" not displayed on Techstream.	B

Go to step 3

A

2.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) BRANCH WIRE)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
A70-25 (CANH) - A70-14 (CANL)*1
A71-25 (CANH) - A71-14 (CANL)*2
Ignition switch off
54 to 69 Ω
*1: w/ VSC
*2: w/o VSC
Text in Illustration
*A
w/ VSC
*B
w/o VSC
*a
Front view of wire harness connector
(to Skid Control ECU (Brake Actuator Assembly))
Result
Result
Proceed to
NG
A
OK (w/ VSC)
B
OK (w/o VSC)
C

Text in Illustration
*A	w/ VSC
*B	w/o VSC
*a	Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly))

Result
Result	Proceed to
NG	A
OK (w/ VSC)	B
OK (w/o VSC)	C

Reconnect the A70*1 or A71*2 skid control ECU (brake actuator assembly) connector.

*1: w/ VSC
*2: w/o VSC

REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) (YARIS_NCP93 RM000001BXP02KX.html)

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY) BRANCH WIRE)

3.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY)

Disconnect the D130 air conditioning amplifier assembly connector.

Select "Communication Bus Check" on the Techstream (YARIS_NCP93 RM000001RSW02LX.html).
Result
Result
Proceed to
"Air Conditioning Amplifier" not displayed on Techstream.
A
Several ECUs and sensors other than "Air Conditioning Amplifier" not displayed on Techstream.
B

Result
Result	Proceed to
"Air Conditioning Amplifier" not displayed on Techstream.	A
Several ECUs and sensors other than "Air Conditioning Amplifier" not displayed on Techstream.	B

Go to step 5

A

4.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH WIRE)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D130-8 (TX+) - D130-9 (TX-)
Ignition switch off
54 to 69 Ω
Text in Illustration
*a
Front view of wire harness connector
(to Air Conditioning Amplifier Assembly)

Text in Illustration
*a	Front view of wire harness connector (to Air Conditioning Amplifier Assembly)

Reconnect the D130 air conditioning amplifier assembly connector.

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY BRANCH WIRE)

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (YARIS_NCP93 RM00000214000EX.html)

5.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIRBAG SENSOR ASSEMBLY)

Disconnect the D112 airbag sensor assembly connector.

Select "Communication Bus Check" on the Techstream (YARIS_NCP93 RM000001RSW02LX.html).
Result
Result
Proceed to
"Airbag" not displayed on Techstream.
A
Several ECUs and sensors other than "Airbag" not displayed on Techstream.
B

Result
Result	Proceed to
"Airbag" not displayed on Techstream.	A
Several ECUs and sensors other than "Airbag" not displayed on Techstream.	B

Go to step 7

A

6.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D112-13 (CANH) - D112-22 (CANL)
Ignition switch off
54 to 69 Ω
Text in Illustration
*a
Front view of wire harness connector
(to Airbag sensor Assembly)

Text in Illustration
*a	Front view of wire harness connector (to Airbag sensor Assembly)

Reconnect the D112 airbag sensor assembly connector.

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

REPLACE AIRBAG SENSOR ASSEMBLY (YARIS_NCP93 RM000000V6U02AX.html)

7.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY))

HINT:

For vehicles without VSC, go to step 9.

Disconnect the D122 steering angle sensor (spiral cable sub-assembly) connector.

Select "Communication Bus Check" on the Techstream (YARIS_NCP93 RM000001RSW02LX.html).
Result
Result
Proceed to
"Spiral cable (Steering Angle Sensor)" not displayed on Techstream.
A
Several ECUs and sensors other than "Spiral cable (Steering Angle Sensor)" not displayed on Techstream.
B

Go to step 9

A

8.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY) BRANCH WIRE)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D122-4 (CANH) - D122-3 (CANL)
Ignition switch off
54 to 69 Ω
Text in Illustration
*a
Front view of wire harness connector
(to Steering Angle Sensor (Spiral Cable Sub-assembly))

Reconnect the D122 steering angle sensor (spiral cable sub-assembly) connector.

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY) BRANCH WIRE)

REPLACE STEERING ANGLE SENSOR (SPIRAL CABLE SUB-ASSEMBLY) (YARIS_NCP93 RM000000SS905CX.html)

9.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

Disconnect the D143 main body ECU (multiplex network body ECU) connector.

Select "Communication Bus Check" on the Techstream (YARIS_NCP93 RM000001RSW02LX.html).
Result
Result
Proceed to
"Main Body" not displayed on Techstream.
A
Several ECUs and sensors other than "Main Body" not displayed on Techstream.
B

Go to step 11

A

10.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) BRANCH WIRE)

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D143-14 (CANH) - D143-13 (CANL)
Ignition switch off
54 to 69 Ω
Text in Illustration
*a
Front view of wire harness connector
(to Main Body ECU (Multiplex Network Body ECU))

Reconnect the D143 main body ECU (multiplex network body ECU) connector.

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) BRANCH WIRE)

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (YARIS_NCP93 RM000003TOE00CX.html)

11.CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)

Disconnect the D104 power steering ECU assembly connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D104-7 (CANH) - D104-8 (CANL)
Ignition switch off
54 to 69 Ω
Text in Illustration
*a
Rear view of wire harness connector
(to Power Steering ECU Assembly)

Reconnect the D104 power steering ECU assembly connector.

REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (POWER STEERING ECU ASSEMBLY BRANCH WIRE)

REPLACE POWER STEERING ECU ASSEMBLY (YARIS_NCP93 RM000002XN603ZX.html)

Tester Connection	Switch Condition	Specified Condition
A70-25 (CANH) - A70-14 (CANL)1 A71-25 (CANH) - A71-14 (CANL)2	Ignition switch off	54 to 69 Ω

Result	Proceed to
"Spiral cable (Steering Angle Sensor)" not displayed on Techstream.	A
Several ECUs and sensors other than "Spiral cable (Steering Angle Sensor)" not displayed on Techstream.	B

Result	Proceed to
"Main Body" not displayed on Techstream.	A
Several ECUs and sensors other than "Main Body" not displayed on Techstream.	B