Part 1

CAN COMMUNICATION: CAN COMMUNICATION SYSTEM: U1002: Lost Communication with Gateway Module

DTC U1002 - Lost Communication with 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/ Rear Power Seat Control System
*2: W/ Rear Power Seat Control System or Seat Heater System
*3: W/ Rear Power Seat Control System (W/ Ottoman)
*4: W/ Dynamic Radar Cruise Control System or Pre-collision System
*5: W/ Power Trunk Lid System
*6: W/ LEXUS Link 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 LINE FOR SHORT CIRCUIT)




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










C -- CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND)
B -- CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR SIDE)
A -- Continue to next step.

3. CHECK FOR OPEN IN CAN MAIN BUS WIRE (NO. 10 JUNCTION CONNECTOR - FRONT CONTROLLER)




(a) Disconnect the L95 No. 10 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. 10 JUNCTION CONNECTOR - REAR JUNCTION BLOCK ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPLACE NO. 10 JUNCTION CONNECTOR
5. CONNECT CONNECTOR
(a) Reconnect the L95 No. 10 junction connector connector.
NEXT -- Continue to next step.

6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 9 JUNCTION CONNECTOR - FRONT CONTROLLER)




(a) Disconnect the R48 No. 9 junction connector connector.
Measure the resistance according to the value(s) in the table below.
Standard resistance:






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

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




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






NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 9 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)
OK -- REPLACE NO. 9 JUNCTION CONNECTOR
8. CONNECT CONNECTOR
(a) Reconnect the R48 No. 9 junction connector connector.
NEXT -- Continue to next step.

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




(a) Disconnect the R57 No. 8 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.

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




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






NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 8 JUNCTION CONNECTOR - NO. 9 JUNCTION CONNECTOR)
OK -- REPLACE NO. 8 JUNCTION CONNECTOR
11. CONNECT CONNECTOR
(a) Reconnect the R57 No. 8 junction connector connector.
NEXT -- Continue to next step.

12. CHECK FOR OPEN IN CAN BUS MAIN WIRE (FRONT CONTROLLER - NO. 8 JUNCTION CONNECTOR)




(a) Disconnect the A50 front controller 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 FRONT CONTROLLER (FRONT CONTROLLER - NO. 8 JUNCTION CONNECTOR)
OK -- REPLACE FRONT CONTROLLER
13. CONNECT CONNECTOR
(a) Reconnect the L95 No. 10 junction connector connector.
NEXT -- Continue to next step.

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




(a) Disconnect the S59 No. 12 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.

15. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 12 JUNCTION CONNECTOR - REAR JUNCTION BLOCK ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPLACE NO. 12 JUNCTION CONNECTOR
16. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

17. CHECK FOR OPEN IN CAN BUS MAIN WIRE (REAR JUNCTION BLOCK ECU - NO. 12 JUNCTION CONNECTOR)




(a) Disconnect the S62 rear junction block 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 REAR JUNCTION BLOCK ECU (REAR JUNCTION BLOCK ECU - NO. 12 JUNCTION CONNECTOR)
OK -- REPLACE REAR JUNCTION BLOCK ECU
18. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

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




(a) Disconnect the S60 No. 11 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. 10 JUNCTION CONNECTOR - NO. 11 JUNCTION CONNECTOR)
OK -- Continue to next step.

20. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 11 JUNCTION CONNECTOR - NO. 12 JUNCTION CONNECTOR)




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






NG -- REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 11 JUNCTION CONNECTOR - NO. 12 JUNCTION CONNECTOR)
OK -- REPLACE NO. 11 JUNCTION CONNECTOR
21. CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR SIDE)




(a) Disconnect the S59 No. 12 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.

22. CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - REAR POWER SEAT MODULE SWITCH)
NOTE:
For vehicles without rear power seat control system or seat heater system and rear power seat control system (W/ ottoman), go to "CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - POWER TRUNK LID CONTROL ECU)".




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






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

23. CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - POWER TRUNK LID CONTROL ECU)
NOTE:
For vehicles without power trunk lid system, go to "CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - REAR JUNCTION BLOCK ECU)".




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






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

24. CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - REAR JUNCTION BLOCK ECU)




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






NG -- CONNECT CONNECTOR
OK -- REPAIR OR REPLACE NO. 12 JUNCTION CONNECTOR
25. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

26. CHECK FOR SHORT IN CAN BUS WIRES (REAR POWER SEAT MODULE SWITCH)




(a) Disconnect the S15* rear power seat module switch connector.
(b) Disconnect the r2 rear power seat module switch connector.
(c) Measure the resistance according to the value(s) in the table below.

Result





HINT: *: W/ Ottoman

C -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO REAR POWER SEAT MODULE SWITCH (CANP, CANN)
B -- REPLACE REAR POWER SEAT MODULE SWITCH
A -- REPLACE REAR POWER SEAT MODULE SWITCH
27. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

28. CHECK FOR SHORT IN CAN BUS WIRES (POWER TRUNK LID CONTROL ECU)




(a) Disconnect the S43 power trunk lid 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 POWER TRUNK LID CONTROL ECU (CANH, CANL)
OK -- REPLACE POWER TRUNK LID CONTROL ECU
29. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

30. CHECK FOR SHORT IN CAN BUS WIRES (REAR JUNCTION BLOCK ECU)




(a) Disconnect the S62 rear junction block 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 REAR JUNCTION BLOCK ECU (NO. 8 JUNCTION CONNECTOR - REAR JUNCTION BLOCK ECU)
OK -- REPLACE REAR JUNCTION BLOCK ECU
31. CONNECT CONNECTOR
(a) Reconnect the S59 No. 12 junction connector connector.
NEXT -- Continue to next step.

32. CHECK FOR SHORT IN CAN BUS WIRES (NO. 12 JUNCTION CONNECTOR - NO. 11 JUNCTION CONNECTOR)




(a) Disconnect the S60 No. 11 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. 12 JUNCTION CONNECTOR - NO. 11 JUNCTION CONNECTOR)
OK -- Continue to next step.

33. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 JUNCTION CONNECTOR SIDE)




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






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

34. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 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. 11 JUNCTION CONNECTOR - FRONT POWER SEAT ECU AND SWITCH LH)".




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






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

35. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 JUNCTION CONNECTOR - FRONT POWER SEAT ECU AND SWITCH LH)




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






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

36. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 JUNCTION CONNECTOR - FRONT POWER SEAT ECU AND SWITCH LH)




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






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

37. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 JUNCTION CONNECTOR - REAR MULTIPLEX NETWORK DOOR ECU LH)




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






NG -- CONNECT CONNECTOR
OK -- REPAIR OR REPLACE NO. 11 JUNCTION CONNECTOR
38. CONNECT CONNECTOR
(a) Reconnect the S60 No. 11 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 (CANP, CANN)
OK -- REPLACE DRIVING SUPPORT ECU
40. CONNECT CONNECTOR
(a) Reconnect the S60 No. 11 junction connector connector.
NEXT -- Continue to next step.

41. CHECK FOR SHORT IN CAN BUS WIRES (FRONT POWER SEAT ECU AND SWITCH LH)




(a) Disconnect the e46 front power seat ECU and switch LH connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO FRONT POWER SEAT ECU AND SWITCH LH (CANP, CANN)
OK -- REPLACE FRONT POWER SEAT ECU AND SWITCH LH
42. CONNECT CONNECTOR
(a) Reconnect the S60 No. 11 junction connector connector.
NEXT -- Continue to next step.

43. CHECK FOR SHORT IN CAN BUS WIRES (FRONT MULTIPLEX NETWORK DOOR ECU LH)




(a) Disconnect the N10 front multiplex network door ECU LH connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO FRONT MULTIPLEX NETWORK DOOR ECU LH (CANP, CANN)
OK -- REPLACE FRONT MULTIPLEX NETWORK DOOR ECU LH
44. CONNECT CONNECTOR
(a) Reconnect the S60 No. 11 junction connector connector.
NEXT -- Continue to next step.

45. CHECK FOR SHORT IN CAN BUS WIRES (REAR MULTIPLEX NETWORK DOOR ECU LH)




(a) Disconnect the O14 rear multiplex network door ECU LH connector.
(b) Measure the resistance according to the value(s) in the table below.

Result





NG -- REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO REAR MULTIPLEX NETWORK DOOR ECU LH (CANP, CANN)
OK -- REPLACE REAR MULTIPLEX NETWORK DOOR ECU LH
46. CONNECT CONNECTOR
(a) Reconnect the S60 No. 11 junction connector connector.
NEXT -- Continue to next step.

47. CHECK FOR SHORT IN CAN BUS WIRES (NO. 11 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)




(a) Disconnect the L95 No. 10 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. 11 JUNCTION CONNECTOR - NO. 10 JUNCTION CONNECTOR)
OK -- Continue to next step.