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DTC B1000: Communication Circuit Error (BUS-OFF)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A  ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch to LOCK (0) and then back to ON (II).
  3. Wait for at least 6 seconds.
  4. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Go to step  5.

    NO  -Intermittent failure, the system is OK at this time. Check for loose or poor connections, or worn/shorted wires. If the connections are good, check the 12 volt battery condition (see 12 VOLT BATTERY TEST ) and the charging system.

  5. Turn the ignition switch to LOCK (0).
  6. Disconnect the appropriate connector at each control unit in the table.
    CONTROL UNIT CONNECTOR REFERENCE

    Unit Connector
    Gauge control module 32P connector
    Climate control unit 36P connector
    HandsFreeLink control unit(1) 28P connector
    Immobilizer-keyless control unit 7P connector
    (1) With HandsFreeLink system
  7. Turn the ignition switch to ON (II).
  8. Clear the DTCs with the HDS.
  9. Turn the ignition switch to LOCK (0) and then back to ON (II).
  10. Wait for at least 6 seconds.
  11. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Go to step  12.

    NO  -Turn the ignition switch to LOCK (0), then go to step  15.

  12. Turn the ignition switch to LOCK (0).
  13. Disconnect the under-dash fuse/relay box connector Y (16P).
  14. Check for continuity between under-dash fuse/relay box connector Y (16P) terminal No. 6 and body ground.
    Fig 1: Checking Continuity Between Under-Dash Fuse/Relay Box Connector Y (16P) Terminal No. 6 And Body Ground
    G06953869Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire between the under-dash fuse/relay box connector and the affected control unit.

    NO  -Faulty MICU; replace the under-dash fuse/relay box.

  15. Reconnect the gauge control module 32P connector.
  16. Turn the ignition switch to ON (II).
  17. Clear the DTCs with the HDS.
  18. Turn the ignition switch to LOCK (0) and then back to ON (II).
  19. Wait for at least 6 seconds.
  20. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

    NO  -Go to step  21.

  21. Reconnect the climate control unit 36P connector.
  22. Turn the ignition switch to ON (II).
  23. Clear the DTCs with the HDS.
  24. Turn the ignition switch to LOCK (0) and then back to ON (II).
  25. Wait for at least 6 seconds.
  26. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Replace the climate control unit (see CLIMATE CONTROL UNIT REMOVAL/INSTALLATION ).

    NO  -

  27. Reconnect the HandsFreeLink control unit 28P connector.
  28. Turn the ignition switch to ON (II).
  29. Clear the DTCs with the HDS.
  30. Turn the ignition switch to LOCK (0) and then back to ON (II).
  31. Wait for at least 6 seconds.
  32. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Replace the HandsFreeLink control unit (see CONTROL UNIT INPUT TEST/REPLACEMENT ).

    NO  -Replace the immobilizer-keyless control unit (see PROGRAMMING IMMOBILIZER-KEYLESS CONTROL UNIT ).