B2326
CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: B2326: CAN MS Bus Line Communication Malfunction
B2326 - CAN MS Bus Line Communication Malfunction
DESCRIPTION
* The main body ECU will store this DTC when no signals can be received from the ECUs that have been memorized as those that are connected to the CAN MS bus.
* When the main body ECU receives response signals from the ECUs connected to the CAN MS bus, the main body ECU recognizes and memorizes that the ECUs are connected to the CAN MS bus. Based on this memorized data, the main body ECU monitors for malfunctions in the ECUs connected to the CAN MS bus when communicating with those ECUs. If the main body ECU cannot receive response signals from the ECUs that have been memorized as those connected to the CAN MS bus, the main body ECU determines that a malfunction exists.
WIRING DIAGRAM
INSPECTION PROCEDURE
NOTICE:
* Turn the engine switch off before measuring the resistance of CAN bus main wires and CAN bus branch wires.
* After the engine 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 engine 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 engine switch, any switches, or any doors 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 will help determine the cause of the malfunction.
PROCEDURE
1. CHECK CAN MS BUS WIRE
(a) Turn the engine switch off.
(b) Measure the resistance according to the value(s) in the table below.
Result:
C -- CHECK FOR SHORT IN CAN MS BUS WIRES (CAN NO. 3 J/C BRANCH WIRE)
B -- CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CERTIFICATION ECU MAIN WIRE)
A -- Continue to next step.
2. CHECK FOR SHORT TO +B IN CAN MS BUS WIRE
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CAN NO. 3 J/C BRANCH WIRE)
OK -- Continue to next step.
3. CHECK FOR SHORT TO GND IN CAN MS BUS WIRE
(a) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CAN NO. 3 J/C BRANCH WIRE)
OK -- Continue to next step.
4. CHECK CAN MS BUS BRANCH WIRE
(a) Check for an open in the branch wires of all ECUs connected to the CAN MS bus.
(1) Check the outer mirror control ECU branch wire B1276.
(2) Check the multiplex tilt and telescopic ECU branch wire B1213.
(3) Check the seat position control ECU (front LH side) branch wire B1272.
(4) Check the seat position control ECU (front RH side) branch wire B1289.
(5) Check the clearance warning ECU branch wire B1297.
Result:
B -- REPAIR OR REPLACE MALFUNCTIONING PART
A -- REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)
5. CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CERTIFICATION ECU MAIN WIRE)
(a) Disconnect certification ECU main wire connector E50 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (MAIN BODY ECU MAIN WIRE)
NG -- Continue to next step.
6. CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (CERTIFICATION ECU - CAN NO. 3 J/C)
(a) Reconnect certification ECU main wire connector E50 to the CAN No. 3 J/C.
(b) Disconnect connector E13 from the certification ECU.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE CERTIFICATION ECU
OK -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU - CAN NO. 3 J/C)
7. CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (MAIN BODY ECU MAIN WIRE)
(a) Reconnect certification ECU main wire connector E50 to the CAN No. 3 J/C.
(b) Disconnect main body ECU main wire connector E49 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE CAN NO. 3 J/C
NG -- Continue to next step.
8. CHECK FOR OPEN IN CAN MS BUS MAIN WIRE (MAIN BODY ECU - CAN NO. 3 J/C)
(a) Reconnect main body ECU main wire connector E49 to the CAN No. 3 J/C.
(b) Disconnect connector E59 from the main body ECU.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)
OK -- REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)
9. CHECK FOR SHORT IN CAN MS BUS WIRES (CAN NO. 3 J/C BRANCH WIRE)
(a) Connect the probes of an ohmmeter to terminals 1 (CANH) and 2 (CANL) of main body ECU main wire connector E49.
(b) While observing the resistance value shown on the tester, disconnect connectors E51, E52, M13, M14, and L17 from the CAN No. 3 J/C one by one until the resistance becomes normal (between 54 and 69 Ohms).
HINT
Disconnect the branch wire connectors only.
Wiring color:
NOTICE:
Do not reconnect the disconnected connectors until this inspection is complete because there may be a short in 2 or more branch wires.
HINT
* (*1) : w/ seat position memory system
* (*2) : w/ intuitive parking assist system
Result:
(c) When there is a short in one or more of the branch wires:
(1) Reconnect all of the connectors to the CAN No. 3 J/C, except for the one that was disconnected last (the short-circuited bus wire). Check that the resistance shown on the tester is normal (between 54 and 69 Ohms) to confirm that there is a short in one branch wire only.
HINT
* The connectors connected to the CAN No. 3 J/C can be distinguished according to the color of the communication bus wires and the shape of the connectors.
* Reconnecting the connectors to non-specified positions on the CAN No. 3 J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.
B -- RECONNECT CONNECTOR
A -- Continue to next step.
10. CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU MAIN WIRE)
(a) Disconnect certification ECU main wire connector E50 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- CHECK FOR SHORT IN CAN MS BUS WIRES (MAIN BODY ECU MAIN WIRE)
NG -- Continue to next step.
11. CHECK FOR SHORT IN CAN MS BUS WIRES (CERTIFICATION ECU - CAN NO. 3 J/C)
(a) Disconnect connector E13 from the certification ECU.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPLACE CERTIFICATION ECU
OK -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CERTIFICATION ECU - CAN NO. 3 J/C)
12. CHECK FOR SHORT IN CAN MS BUS WIRES (MAIN BODY ECU MAIN WIRE)
(a) Reconnect certification ECU main wire connector E50 to the CAN No. 3 J/C.
(b) Disconnect main body ECU main wire connector E49 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE CAN NO. 3 J/C
NG -- Continue to next step.
13. CHECK FOR SHORT IN CAN MS BUS WIRES (MAIN BODY ECU - CAN NO. 3 J/C)
(a) Disconnect connector E59 from the main body ECU.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)
OK -- REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)
14. CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (CAN NO. 3 J/C BRANCH WIRE)
(a) Disconnect connectors from the CAN No. 3 J/C one at a time.
NOTICE:
Disconnect the ECU and sensor connectors other than main body ECU main wire connector E49.
(b) Using an ohmmeter, measure the resistance between terminal 1 (CANH) of main body ECU main wire connector E49 and terminal 16 (BAT) of the DLC3, and between terminal 2 (CANL) of main body ECU main wire connector E49 and terminal 16 (BAT) of the DLC3 each time a connector is disconnected.
Wiring color:
Wiring color:
NOTICE:
Do not reconnect the disconnected connectors until this inspection is complete because there may be a short to B+ in 2 or more CAN MS bus wires.
HINT
* (*1) : w/ seat position memory system
* (*2) : w/ intuitive parking assist system
Result:
(c) When there is a short to B+ in one or more of the bus wires that connect to an ECU (or sensor):
(1) Reconnect all of the connectors to the CAN No. 3 J/C, except for the one that was disconnected last (the bus wire that is shorted to B+). Check that the resistance shown on the tester is normal (6 kOhms or more) to confirm that there is a short to B+ in one bus wire only.
HINT
* The connectors connected to the CAN No. 3 J/C can be distinguished according to the color of the communication bus wires and the shape of the connectors.
* Reconnecting the connectors to non-specified positions on the CAN No. 3 J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.
B -- RECONNECT CONNECTOR
A -- Continue to next step.
15. CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (MAIN BODY ECU MAIN WIRE)
(a) Disconnect main body ECU main wire connector E49 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE CAN NO. 3 J/C
NG -- Continue to next step.
16. CHECK FOR SHORT TO +B IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)
(a) Disconnect connector E59 from the main body ECU.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)
OK -- REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)
17. CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (CAN NO. 3 J/C BRANCH WIRE)
(a) Disconnect connectors from the CAN No. 3 J/C one at a time.
NOTICE:
Disconnect the ECU and sensor connectors other than main body ECU main wire connector E49.
(b) Using an ohmmeter, measure the resistance between terminal 1 (CANH) of main body ECU main wire connector E49 and terminal 4 (CG) of the DLC3, and between terminal 2 (CANL) of main body ECU main wire connector E49 and terminal 4 (CG) of the DLC3 each time a connector is disconnected.
Wiring color:
Wiring color:
NOTICE:
Do not reconnect the disconnected connectors until this inspection is complete because there may be a short to GND in 2 or more CAN MS bus wires.
HINT
* (*1) : w/ seat position memory system
* (*2) : w/ intuitive parking assist system
Result:
(c) When there is a short to GND in one or more of the bus wires that connect to an ECU (or sensor):
(1) Reconnect all of the connectors to the CAN No. 3 J/C, except for the one that was disconnected last (the bus wire that is shorted to GND). Check that the resistance shown on the tester is normal (200 Ohms or more) to confirm that there is a short to GND in one bus wire only.
HINT
* The connectors connected to the CAN No. 3 J/C can be distinguished according to the color of the communication bus wires and the shape of the connectors.
* Reconnecting the connectors to non-specified positions on the CAN No. 3 J/C does not affect system operation. However, it is preferred to reconnect the connectors to their specified positions to avoid negative effects on the wiring such as tension on the wiring harnesses, and to make future maintenance easier.
B -- RECONNECT CONNECTOR
A -- Continue to next step.
18. CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (MAIN BODY ECU MAIN WIRE)
(a) Disconnect main body ECU main wire connector E49 from the CAN No. 3 J/C.
HINT
* Before disconnecting the connector, make a note of where it is connected.
* Reconnect the connector to its original position.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
OK -- REPLACE CAN NO. 3 J/C
NG -- Continue to next step.
19. CHECK FOR SHORT TO GND IN CAN MS BUS WIRE (MAIN BODY ECU - CAN NO. 3 J/C)
(a) Disconnect connector E59 from the main body ECU.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:
NG -- REPAIR OR REPLACE CAN MS BUS MAIN WIRE OR CONNECTOR (CAN NO. 3 J/C - MAIN BODY ECU)
OK -- REPLACE INSTRUMENT PANEL J/B (MAIN BODY ECU)
20. RECONNECT CONNECTOR
(a) Reconnect the connector for the short-circuited main or branch wire to the CAN No. 3 J/C (the connector that caused the bus wire resistance to become normal when it was disconnected).
NEXT -- Continue to next step.
21. CHECK FOR SHORT IN CAN MS BUS WIRES
(a) Disconnect the connector of the ECU that is connected to the short-circuited main or branch wire from the ECU.
(b) Recheck the short-circuited wire with the connector disconnected from the ECU.
Standard:
The wire is not short-circuited.
HINT
If the short-circuited wire returns to normal after being disconnected from the ECU, an internal ECU short-circuit is suspected.
NG -- REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BRANCH WIRE OR CONNECTOR
OK -- REPLACE CORRESPONDING ECU OR SENSOR