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U1004








CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: U1004: Lost Communication with Engine Gateway Module

DTC U1004 - Lost Communication with Engine Gateway Module

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.)





HINT:
*1: W/ Dynamic Radar Cruise Control System or Pre-collision System
*2: W/ Air Suspension System
*3: W/ Variable Gear Ratio Steering System
*4: W/ Advanced Parking Guidance System and Intuitive Parking Assist System
*5: W/ Intuitive Parking Assist 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 prevent airbag and seat belt pretensioner activation.
NOTICE:
- After the engine switch is turned off, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the engine switch off, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.
- 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 LINES FOR SHORT CIRCUIT)




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










C -- CHECK HARNESS AND CONNECTOR (ECM - BATTERY AND BODY GROUND)
B -- CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR SIDE)
A -- Continue to next step.

3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 7 JUNCTION CONNECTOR - ELECTRIC PARKING BRAKE ECU)




(a) Disconnect the A66 No. 7 junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 7 JUNCTION CONNECTOR - POWER STEERING ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPLACE NO. 7 JUNCTION CONNECTOR
5. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (POWER STEERING ECU - NO. 7 JUNCTION CONNECTOR)




(a) Disconnect the A44 power steering ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO POWER STEERING ECU (POWER STEERING ECU - NO. 7 JUNCTION CONNECTOR)
OK -- REPLACE POWER STEERING ECU
7. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

8. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 6 JUNCTION CONNECTOR - NO. 7 JUNCTION CONNECTOR)




(a) Disconnect the A65 No. 6 junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 JUNCTION CONNECTOR - NO. 7 JUNCTION CONNECTOR)
OK -- Continue to next step.

9. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 6 JUNCTION CONNECTOR - ELECTRIC PARKING BRAKE ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPLACE NO. 6 JUNCTION CONNECTOR
10. CONNECT CONNECTOR
(a) Reconnect the A65 No. 6 junction connector connector.
NEXT -- Continue to next step.

11. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ELECTRIC PARKING BRAKE ECU - NO. 6 JUNCTION CONNECTOR)




(a) Disconnect the S48 electric parking brake ECU connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ELECTRIC PARKING BRAKE ECU (ELECTRIC PARKING BRAKE ECU - NO. 6 JUNCTION CONNECTOR)
OK -- REPLACE ELECTRIC PARKING BRAKE ECU
12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR SIDE)




(a) Disconnect the A66 No. 7 junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - SUSPENSION CONTROL ECU)
NOTE:
For vehicles without air suspension system, go to " CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - STEERING CONTROL ECU)".




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

14. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - STEERING CONTROL ECU)
NOTE:
For vehicles without variable gear ratio steering system, go to " CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - PARKING ASSIST ECU)".




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

15. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - PARKING ASSIST ECU)
NOTE:
For vehicles without advanced parking guidance system and intuitive parking assist system, go to " CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - CLEARANCE WARNING ECU)".




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

16. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - CLEARANCE WARNING ECU)
NOTE:
For vehicles without intuitive parking assist system, go to " CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - POWER STEERING ECU)".




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

17. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - POWER STEERING ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPAIR OR REPLACE NO. 7 JUNCTION CONNECTOR
18. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

19. CHECK FOR SHORT IN CAN BUS WIRES (SUSPENSION CONTROL ECU)




(a) Disconnect the R1 suspension control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SUSPENSION CONTROL ECU (CA2H, CA2L)
OK -- REPLACE SUSPENSION CONTROL ECU
20. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

21. CHECK FOR SHORT IN CAN BUS WIRES (STEERING CONTROL ECU)




(a) Disconnect the A42 steering control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO STEERING CONTROL ECU (CA2H, CA2L)
OK -- REPLACE STEERING CONTROL ECU
22. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

23. CHECK FOR SHORT IN CAN BUS WIRES (PARKING ASSIST ECU)




(a) Disconnect the L90 parking assist ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO PARKING ASSIST ECU (CA2H, CA2L)
OK -- REPLACE PARKING ASSIST ECU
24. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

25. CHECK FOR SHORT IN CAN BUS WIRES (CLEARANCE WARNING ECU)




(a) Disconnect the L19 clearance warning ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO CLEARANCE WARNING ECU (CA2H, CA2L)
OK -- REPLACE CLEARANCE WARNING ECU
26. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

27. CHECK FOR SHORT IN CAN BUS WIRES (POWER STEERING ECU)




(a) Disconnect the A44 power steering ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO POWER STEERING ECU (NO. 7 JUNCTION CONNECTOR - POWER STEERING ECU)
OK -- REPLACE POWER STEERING ECU
28. CONNECT CONNECTOR
(a) Reconnect the A66 No. 7 junction connector connector.
NEXT -- Continue to next step.

29. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 JUNCTION CONNECTOR - NO. 6 JUNCTION CONNECTOR)




(a) Disconnect the A65 No. 6 junction connector connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard resistance:






NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 7 JUNCTION CONNECTOR - NO. 6 JUNCTION CONNECTOR)
OK -- Continue to next step.

30. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 JUNCTION CONNECTOR - SKID CONTROL ECU)




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

31. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 JUNCTION CONNECTOR - ECM)




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

32. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 JUNCTION CONNECTOR - DRIVING SUPPORT ECU)
NOTE:
For vehicles without dynamic radar cruise control System or pre-collision system, go to " CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 JUNCTION CONNECTOR - ELECTRIC PARKING BRAKE ECU)".




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






NG -- CONNECT CONNECTOR
OK -- Continue to next step.

33. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 JUNCTION CONNECTOR - ELECTRIC PARKING BRAKE ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPAIR OR REPLACE NO. 6 JUNCTION CONNECTOR
34. CONNECT CONNECTOR
(a) Reconnect the A65 No. 6 junction connector connector.
NEXT -- Continue to next step.

35. CHECK FOR SHORT IN CAN BUS WIRES (SKID CONTROL ECU)




(a) Disconnect the A19 skid control ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO SKID CONTROL ECU (CA2H, CA2L)
OK -- REPLACE SKID CONTROL ECU
36. CONNECT CONNECTOR
(a) Reconnect the A65 No. 6 junction connector connector.
NEXT -- Continue to next step.

37. CHECK FOR SHORT IN CAN BUS WIRES (ECM)




(a) Disconnect the A13 ECM connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO ECM (CA2H, CA2L)
OK -- REPLACE ECM
38. CONNECT CONNECTOR
(a) Reconnect the A65 No. 6 junction connector connector.
NEXT -- Continue to next step.

39. CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT ECU)




(a) Disconnect the A33 driving support ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DRIVING SUPPORT ECU (CA2H, CA2L)
OK -- REPLACE DRIVING SUPPORT ECU
40. CONNECT CONNECTOR
(a) Reconnect the A65 No. 6 junction connector connector.
NEXT -- Continue to next step.

41. CHECK FOR SHORT IN CAN BUS WIRES (ELECTRIC PARKING BRAKE ECU)




(a) Disconnect the S48 electric parking brake ECU connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ELECTRIC PARKING BRAKE ECU (NO. 6 JUNCTION CONNECTOR - ELECTRIC PARKING BRAKE ECU)
OK -- REPLACE ELECTRIC PARKING BRAKE ECU
42. CHECK HARNESS AND CONNECTOR (ECM - BATTERY AND BODY GROUND)




(a) Connect the cable to the negative (-) battery terminal.
NOTE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected Repair Instruction - Initialization.
(b) Disconnect the A13, A14, E2 and E3 ECM connectors.
(c) Measure the resistance according to the value(s) in the table below.
Standard resistance:





(d) Measure the voltage according to the value(s) in the table below.
Standard voltage:






NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- REPLACE ECM
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