FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Open in One Side of CAN Branch Line





CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Open in One Side of CAN Branch Line
- Open in One Side of CAN Branch Line

DESCRIPTION

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





WIRING DIAGRAM









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.

HINT
* 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 power steering ECU 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 power steering ECU, 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.

PROCEDURE

1. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (ABS AND TRACTION ACTUATOR (SKID CONTROL ECU))

(a) Disconnect the A15 ABS and traction actuator (skid control ECU) connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER)
A -- Continue to next step.

2. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (ABS AND TRACTION ACTUATOR (SKID CONTROL ECU) BRANCH WIRE)

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





HINT
The resistance must be measured after the A15 ABS and traction actuator (skid control ECU) connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO ABS AND TRACTION ACTUATOR (SKID CONTROL ECU (CAN-H, CAN-L))

OK -- REPLACE ABS AND TRACTION ACTUATOR (SKID CONTROL ECU) Removal

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

(a) Disconnect the G7 air conditioning amplifier connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (CENTER AIRBAG SENSOR ASSEMBLY)
A -- Continue to next step.

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

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





HINT
The resistance must be measured after the G7 air conditioning amplifier connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AIR CONDITIONING AMPLIFIER (CAN-H, CAN-L)

OK -- REPLACE AIR CONDITIONING AMPLIFIER Removal

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

(a) Disconnect the F18 center airbag sensor assembly connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING SENSOR)
A -- Continue to next step.

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

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





HINT
The resistance must be measured after the F18 center airbag sensor assembly connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO CENTER AIRBAG SENSOR ASSEMBLY (CAN-H, CAN-L)

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

7. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING SENSOR)

(a) Disconnect the F33 steering sensor connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU)
A -- Continue to next step.

8. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING SENSOR BRANCH WIRE)

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





HINT
The resistance must be measured after the F33 steering sensor connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO STEERING SENSOR (CAN-H, CAN-L)

OK -- REPLACE STEERING SENSOR Removal

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

(a) Disconnect the F38 main body ECU connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR)
A -- Continue to next step.

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

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





HINT
The resistance must be measured after the F38 main body ECU connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MAIN BODY ECU (CAN-H, CAN-L)

OK -- REPLACE MAIN BODY ECU

11. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR)

(a) Disconnect the F34 yaw rate sensor connector.





(b) Select "CAN Bus Check" on the Techstream Diagnosis System.

Result:





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (COMBINATION METER ECU BRANCH WIRE)
A -- Continue to next step.

12. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (YAW RATE SENSOR BRANCH WIRE)

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





HINT
The resistance must be measured after the F34 yaw rate sensor connector is disconnected.

Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO YAW RATE SENSOR (CAN-H, CAN-L)

OK -- REPLACE YAW RATE SENSOR Removal

13. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (COMBINATION METER ECU BRANCH WIRE)

(a) Disconnect the F2 combination meter ECU connector.

(b) Measure the resistance.





Standard resistance:





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO COMBINATION METER (CAN-H, CAN-L)

OK -- REPLACE COMBINATION METER ASSEMBLY Removal