Check CAN Bus Line for Short to +B
CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: Check CAN Bus Line for Short to +B
- Check CAN Bus Line for Short to +B
DESCRIPTION
There may be a short circuit between the CAN bus line and +B when there is resistance between terminals 6 (CANH) and 16 (BAT) or terminals 14 (CANL) and 16 (BAT) of the DLC3.
* *1: for Hydraulic Booster Type
* *2: for Vacuum Booster Type
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
* Turn the ignition switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.
* Turn the ignition switch off before inspecting CAN bus wires for a ground short.
* After the ignition switch is turned off, check that the key reminder warning system is 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 any doors need to be opened in order to check connectors, open the doors and leave them open.
HINT
* Operating the ignition switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.
* Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.
PROCEDURE
1. PRECAUTION
NOTICE:
After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Service Precautions.
NEXT -- Continue to next step.
2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL
(a) Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
NEXT -- Continue to next step.
3. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (DLC3 BRANCH WIRE)
(a) Disconnect the J19 No. 1 CAN junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CAN-H, CAN-L)
OK -- Continue to next step.
4. CONNECT CONNECTOR
(a) Reconnect the J19 No. 1 CAN junction connector connector.
NEXT -- Continue to next step.
5. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR SIDE)
(a) Disconnect the J18 No. 2 CAN junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- CONNECT CONNECTOR
OK -- Continue to next step.
6. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR - SKID CONTROL ECU)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
Result
B -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (MASTER CYLINDER SOLENOID (SKID CONTROL ECU))
C -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU))
A -- Continue to next step.
7. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (COMBINATION METER ASSEMBLY)
OK -- REPLACE NO. 2 CAN JUNCTION CONNECTOR
8. CONNECT CONNECTOR
(a) Reconnect the J18 No. 2 CAN junction connector connector.
NEXT -- Continue to next step.
9. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR)
(a) Disconnect the J19 No. 1 CAN junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- Continue to next step.
10. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR - STEERING ANGLE SENSOR)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (STEERING ANGLE SENSOR)
OK -- Continue to next step.
11. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR - CENTER AIRBAG SENSOR ASSEMBLY)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY)
OK -- Continue to next step.
12. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR - YAW RATE AND DECELERATION SENSOR)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (YAW RATE AND DECELERATION SENSOR)
OK -- Continue to next step.
13. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 1 CAN JUNCTION CONNECTOR - ECM)
(a) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
Result
B -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECM)
C -- CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECM)
A -- REPLACE NO. 1 CAN JUNCTION CONNECTOR
14. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (MASTER CYLINDER SOLENOID (SKID CONTROL ECU))
(a) Disconnect the S1 master cylinder solenoid (skid control ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE MASTER CYLINDER SOLENOID (SKID CONTROL ECU) Disassembly
15. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU))
(a) Disconnect the S1 brake actuator assembly (skid control ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) Removal
16. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (COMBINATION METER ASSEMBLY)
(a) Disconnect the C9 combination meter assembly (combination meter ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE COMBINATION METER ASSEMBLY Removal
17. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (STEERING ANGLE SENSOR)
(a) Disconnect the S9 steering angle sensor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE STEERING ANGLE SENSOR Removal
18. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY)
(a) Disconnect the A21 center airbag sensor assembly connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal
19. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (YAW RATE AND DECELERATION SENSOR)
(a) Disconnect the Y1 yaw rate and deceleration sensor connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE YAW RATE AND DECELERATION SENSOR Removal
20. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECM)
(a) Disconnect the E14 ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE ECM Removal
21. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECM)
(a) Disconnect the E7 ECM connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Text in Illustration
NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CAN-H, CAN-L)
OK -- REPLACE ECM Removal