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DTC B1000: Communication Bus Line 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 6 seconds or more.
  4. Check for DTCs with the HDS.

    Is DTC B1000 indicated? 

    YES  -Go to step 5.

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

  5. Check for DTCs with the HDS.

    Are DTCs B1005, B1006, B1007, B1008, B1010, and B1011 also indicated? 

    YES  -Go to step 6.

    NO  -Faulty MICU; replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ). ■

  6. Turn the ignition switch to LOCK (0).
  7. Disconnect the appropriate connector at each control unit in the table one at a time. Clear the DTC, then recheck for DTCs after each unit is disconnected.
    CONNECTOR REFERENCE CHART

    Control unit Connector
    Gauge control module Connector B(14P)
    Relay control module Connector J (10P)
    Door multiplex control unit Power window master switch connector (23P)
    Combination switch control unit Connector (12P)
    HVAC control unit/Climate control unit Connector (30P)
    HandsFreeLink control unit Connector (28P)

    Is DTC B1000 indicated with each individual unit disconnected? 

    YES  -Go to step 8.

    NO  -Check the power and grounds to the control unit that was disconnected when B1000 did not reset. If OK, replace the control unit. ■

  8. Disconnect each control unit connectors in the table.
    CONNECTOR REFERENCE CHART

    Control unit Appropriate connector
    Gauge control module Connector B(14P)
    Relay control module Connector J (10P)
    Door multiplex control unit Power window master switch connector (23P)
    Combination switch control unit Connector (12P)
    HVAC control unit/Climate control unit Connector (30P)
    HandsFreeLink control unit Connector (28P)
  9. Disconnect under-dash fuse/relay box connectors D (17P), J (21P), N (45P), X (39P), and P (30P).
  10. Check for continuity between each of the under-dash fuse/relay box terminals listed in the table and body ground.
    CONNECTOR REFERENCE CHART

    Connected control unit Under-dash fuse/relay box terminal
    Gauge control module N28
    Relay control module D11
    Door multiplex control unit J4
    Combination switch control unit X27
    HVAC control unit/Climate control unit N22
    HandsFreeLink control unit X18

    Is there continuity? 

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

    NO  -Go to step 11.

  11. Measure the voltage between each of the under-dash fuse/relay box terminals listed in the table and body ground.
CONNECTOR REFERENCE CHART

Connected control unit Under-dash fuse/relay box terminal
Gauge control module N28
Relay control module D11
Door multiplex control unit J4
Combination switch control unit X27
HVAC control unit/Climate control unit N22
HandsFreeLink control unit X18

Is there less than 0.2 V? 

YES  -Replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ). ■

NO  -Repair a short to power in the wire between the under-dash fuse/relay box and the affected control unit. ■