Networking. Can Communication System (For Sedan) Can Main Wire For Disconnection

There may be an open circuit in the CAN main wire and/or the DLC3 branch wire when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 69 Ω or higher.

Symptom	Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of DLC3 is 69 Ω or higher.	CAN main wire or connector D-CAN junction connector P-CAN junction connector ECM Power steering ECU

WIRING DIAGRAM

Yaris. Ncp93, 131.Networking.Can Communication System (For Sedan).Can Communication System (For Sedan) Can Main Wire For Disconnection

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.

1.CHECK DLC3

Turn the ignition switch off.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D15-6 (CANH) - D15-14 (CANL)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
DLC3
NOTICE:
When the measured value is 132 Ω or higher and a CAN communication system diagnostic trouble code is output, there may be a fault besides disconnection of the DLC3 branch wire. For that reason, troubleshooting should be performed again from "How to Proceed with Troubleshooting" (YARIS_NCP93 RM000001D3500JX.html) after repairing the trouble area.

Text in Illustration
*1	DLC3

REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CAN-H, CAN-L)

OK

2.CHECK CAN MAIN WIRE FOR DISCONNECTION (D-CAN SIDE)

Turn the ignition switch off.

Disconnect the D42 P-CAN junction connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D42-11 (TOLH) - D42-22 (TOLH)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Rear view of wire harness connector
(to P-CAN Junction Connector)

Text in Illustration
*1	Rear view of wire harness connector (to P-CAN Junction Connector)

Go to step 7

OK

3.CONNECT CONNECTOR

Reconnect the P-CAN junction connector.

NEXT

4.CHECK CAN MAIN WIRE FOR DISCONNECTION (POWER STEERING ECU)

Turn the ignition switch off.

Disconnect the D31 power steering ECU connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D31-1 (CANH) - D31-7 (CANL)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Rear view of wire harness connector
(to Power Steering ECU)

Text in Illustration
*1	Rear view of wire harness connector (to Power Steering ECU)

Result
Result	Proceed to
NG	A
OK	B

REPLACE POWER STEERING ECU (YARIS_NCP93 RM000001EEX046X.html)

A

5.CONNECT CONNECTOR

Reconnect the power steering ECU connector.

NEXT

6.CHECK CAN MAIN WIRE FOR DISCONNECTION (P-CAN J/C - POWER STEERING ECU)

Turn the ignition switch off.

Disconnect the D42 P-CAN junction connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D42-4 (EPS) - D42-15 (EPS)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Rear view of wire harness connector
(to P-CAN Junction Connector)

Text in Illustration
*1	Rear view of wire harness connector (to P-CAN Junction Connector)

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (P-CAN J/C - POWER STEERING ECU (CAN-H, CAN-L))

REPLACE P-CAN JUNCTION CONNECTOR

7.CONNECT CONNECTOR

Reconnect the P-CAN junction connector.

NEXT

8.CHECK CAN MAIN WIRE FOR DISCONNECTION (ECM)

Turn the ignition switch off.

Disconnect the A21 ECM connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
A21-41 (CANH) - A21-49 (CANL)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Front view of wire harness connector
(to ECM)

Text in Illustration
*1	Front view of wire harness connector (to ECM)

Go to step 9

REPLACE ECM (YARIS_NCP93 RM000001CN002AX.html)

9.CONNECT CONNECTOR

Reconnect the ECM connector.

NEXT

10.CHECK CAN MAIN WIRE FOR DISCONNECTION (D-CAN J/C - ECM)

Turn the ignition switch off.

Disconnect the D41 D-CAN junction connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D41-4 (EFI) - D41-15 (EFI)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Rear view of wire harness connector
(to D-CAN Junction Connector)

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (D-CAN J/C - ECM (CAN-H, CAN-L))

OK

11.CHECK CAN MAIN WIRE FOR DISCONNECTION (D-CAN J/C - P-CAN J/C)

Turn the ignition switch off.

Disconnect the D41 D-CAN junction connector.

Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
Switch Condition
Specified Condition
D41-11 (TORH) - D41-22 (TORH)
Ignition switch off
108 to 132 Ω
Text in Illustration
*1
Rear view of wire harness connector
(to D-CAN Junction Connector)

REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (D-CAN J/C - P-CAN J/C (CAN-H, CAN-L))

REPLACE D-CAN JUNCTION CONNECTOR

Tester Connection	Switch Condition	Specified Condition
D15-6 (CANH) - D15-14 (CANL)	Ignition switch off	108 to 132 Ω