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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 "Communication 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.)





HINT:
*: w/ Accessory

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.
- 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 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 combination meter 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 A37 ABS and traction actuator (skid control ECU) connector.
(b) Select "Communication 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 A37 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)
3. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (AIR CONDITIONING AMPLIFIER)




(a) Disconnect the C8 air conditioning amplifier connector.
(b) Select "Communication 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 C8 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
5. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (CENTER AIRBAG SENSOR ASSEMBLY)




(a) Disconnect the C17 center airbag sensor assembly connector.
(b) Select "Communication 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 C17 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
7. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (STEERING SENSOR)




(a) Disconnect the C44 steering sensor connector.
(b) Select "Communication 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 C44 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
9. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (MAIN BODY ECU)




(a) Disconnect the C45 main body ECU connector.
(b) Select "Communication 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 C45 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 C43 yaw rate sensor connector.
(b) Select "Communication Bus Check" on the Techstream Diagnosis System.

Result





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU)
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 C43 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
13. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU)




(a) Disconnect the C34 power steering ECU connector.
(b) Select "Communication Bus Check" on the Techstream Diagnosis System.

Result





B -- CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (ACCESSORY BUS BUFFER BRANCH WIRE)
A -- Continue to next step.
14. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (POWER STEERING ECU BRANCH WIRE)




(a) Measure the resistance according to the value in the table below.
HINT: The resistance must be measured after the C34 certification ECU connector is disconnected.

Standard Resistance:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO POWER STEERING ECU (CAN-H, CAN-L)
OK -- REPLACE POWER STEERING ECU
15. CHECK OPEN IN ONE SIDE OF CAN BRANCH WIRE (ACCESSORY BUS BUFFER BRANCH WIRE)
(a) Disconnect the C26 accessory bus buffer connector.




(b) Measure the resistance according to the value in the table below.
Standard Resistance:






NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO ACCESSORY BUS BUFFER (CAN-H, CAN-L)
OK -- CHECK ACCESSORY CIRCUIT
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