Part 1

NETWORKING: CAN COMMUNICATION SYSTEM: U1002 (CAN MS BUS): Lost Communication with Gateway Module (Main body ECU)
U1002 (CAN MS BUS) - Lost Communication with Gateway Module (Main body ECU)

DESCRIPTION

If 2 or more DTCs are output during the DTC check, one side of the CAN branch wire may be open (One side of the CANH [branch wire]/CANL [branch wire] of the ECU and/or sensor is open).





* *: w/ Tire Pressure Warning System

WIRING DIAGRAM









INSPECTION PROCEDURE

PROCEDURE

1. 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.

NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected Repair Instruction - Initialization

NEXT -- Continue to next step.

2. CHECK CAN BUS WIRE (MAIN WIRE FOR DISCONNECTION, BUS LINE FOR SHORT CIRCUIT)

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





Standard Resistance:





Text in Illustration





Result





C -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND)

B -- CHECK FOR SHORT IN CAN BUS WIRES (NO. 10 JUNCTION CONNECTOR SIDE)
A -- Continue to next step.

3. CHECK FOR OPEN IN MAIN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR - MAIN BODY ECU)

(a) Disconnect the L29 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.

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 CAN JUNCTION CONNECTOR - COMBINATION METER)

(a) Disconnect the L30 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 -- REPAIR OR REPLACE NO. 2 CAN JUNCTION CONNECTOR

5. CONNECT CONNECTOR

(a) Reconnect the L29 No. 2 CAN junction connector connector.

NEXT -- Continue to next step.

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 8 JUNCTION CONNECTOR - MAIN BODY ECU)

(a) Disconnect the E76 No. 8 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.

7. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 8 JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR)

(a) 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 (NO. 8 JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR)

OK -- REPAIR OR REPLACE NO. 8 JUNCTION CONNECTOR

8. CONNECT CONNECTOR

(a) Reconnect the E76 No. 8 junction connector connector.

NEXT -- Continue to next step.

9. CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - NO. 8 JUNCTION CONNECTOR)

(a) Disconnect the E3 main body ECU (cowl side junction block LH) 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 CONNECTED TO MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) (MAIN BODY ECU - NO. 8 JUNCTION CONNECTOR)

OK -- REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)

10. CONNECT CONNECTOR

(a) Reconnect the L29 and L30 No. 2 CAN junction connector connectors.

NEXT -- Continue to next step.

11. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 9 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)

(a) Disconnect the E70 No. 10 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.

12. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 10 JUNCTION CONNECTOR - COMBINATION METER)

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





Standard Resistance:





Text in Illustration





NG -- CONNECT CONNECTOR

OK -- REPAIR OR REPLACE NO. 10 CAN JUNCTION CONNECTOR

13. CONNECT CONNECTOR

(a) Reconnect the E70 No. 10 junction connector connector.

NEXT -- Continue to next step.

14. CHECK FOR OPEN IN CAN BUS MAIN WIRE (COMBINATION METER - NO. 10 JUNCTION CONNECTOR)

(a) Disconnect the E7 combination meter 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 CONNECTED TO COMBINATION METER (COMBINATION METER - NO. 10 JUNCTION BLOCK)

OK -- REPLACE COMBINATION METER ASSEMBLY Removal

15. CONNECT CONNECTOR

(a) Reconnect the E70 No. 10 junction connector connector.

NEXT -- Continue to next step.

16. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 9 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)

(a) Disconnect the E73 No. 9 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 MAIN WIRE OR CONNECTOR (NO. 9 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)
OK -- Continue to next step.

17. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 CAN JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)

(a) 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 (NO. 2 CAN JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)

OK -- REPAIR OR REPLACE NO. 9 JUNCTION CONNECTOR

18. CHECK FOR SHORT IN CAN BUS WIRES (NO. 10 JUNCTION CONNECTOR SIDE)

(a) Disconnect the E70 No. 10 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.

19. CHECK FOR SHORT IN CAN BUS WIRES (NO. 10 JUNCTION CONNECTOR - COMBINATION METER)

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





Standard Resistance:





Text in Illustration





NG -- CONNECT CONNECTOR

OK -- REPAIR OR REPLACE NO. 10 JUNCTION CONNECTOR

20. CONNECT CONNECTOR

(a) Reconnect the E70 No. 10 junction connector connector.

NEXT -- Continue to next step.

21. CHECK FOR SHORT IN CAN BUS WIRES (NO. 10 JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)

(a) Disconnect the E73 No. 9 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 MAIN WIRE OR CONNECTOR (NO. 10 JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)
OK -- Continue to next step.

22. CHECK FOR SHORT IN CAN BUS WIRES (NO. 9 JUNCTION CONNECTOR SIDE)

(a) 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.

23. CHECK FOR SHORT IN CAN BUS WIRES (NO. 9 JUNCTION CONNECTOR - WINDSHIELD WIPER ECU)

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





Standard Resistance:





Text in Illustration





NG -- CONNECT CONNECTOR

OK -- REPAIR OR REPLACE NO. 9 JUNCTION CONNECTOR

24. CONNECT CONNECTOR

(a) Reconnect the E73 No. 9 junction connector connector.

NEXT -- Continue to next step.

25. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 CAN JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)

(a) Disconnect the L30 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 -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)
OK -- Continue to next step.

26. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 CAN JUNCTION CONNECTOR - NO. 8 JUNCTION CONNECTOR)

(a) Disconnect the L29 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 -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR)
OK -- Continue to next step.

27. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 CAN JUNCTION CONNECTOR SIDE)

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





Standard Resistance:





Text in Illustration





Result





C -- CONNECT CONNECTOR

B -- REPLACE NO. 2 CAN JUNCTION CONNECTOR
A -- Continue to next step.

28. CONNECT CONNECTOR

(a) Reconnect the E73 No. 9 junction connector connector.

NEXT -- Continue to next step.

29. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 CAN JUNCTION CONNECTOR - TIRE PRESSURE WARNING ECU)

(a) Disconnect the L31 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 -- REPLACE NO. 2 CAN JUNCTION CONNECTOR