DTC B1000: Communication Bus Line Error
- Clear the DTCs with the HDS.
- Turn the ignition switch to LOCK (0), and then back to ON (II).
- Wait for at least 6 seconds.
- 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 and the charging system.
- Check for DTCs with the HDS.
Are DTCs B1008, B1011, and B1032 also indicated?
YES -Go to step 6.
NO -Faulty MICU; replace the under-dash fuse/relay box (see REMOVAL AND INSTALLATION ).
- Turn the ignition switch to LOCK (0).
- 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 LIST
Unit Connector Gauge control module 36P connector Immobilizer-keyless control unit 7P connector Automatic lighting control unit (if equipped) 14P connector HandsFreeLink control unit (if equipped) 28P connector Climate control unit ('08-10 EX-L models) 36P connector 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 DTC B1000 did not reset. If OK, replace the control unit.
- Disconnect all of the appropriate connectors for each of the units in the table.CONNECTOR LIST
Unit Connector Gauge control module 36P connector Immobilizer-keyless control unit 7P connector Automatic lighting control unit (if equipped) 14P connector HandsFreeLink control unit (if equipped) 28P connector Climate control unit ('08-10 EX-L models) 36P connector - Disconnect under-dash fuse/relay box connector Q (16P).
- Check for continuity between under-dash fuse/relay box connector Q (16P) terminal No. 6 and body ground.Fig 1: Checking Continuity Between Under-Dash Fuse/Relay Box Connector Q (16P) Terminal No. 6 And Body Ground
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Is there continuity?
YES -Repair a short to ground in the wire between the under-dash fuse/relay box and the affected control unit.
NO -Go to step 11.
- Measure the voltage between under-dash fuse/relay box connector Q (16P) terminal No. 6 and body ground.Fig 2: Measuring Voltage Between Under-Dash Fuse/Relay Box Connector Q (16P) Terminal No. 6 And Body Ground
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Is there less than 0.2 V?
YES -Faulty MICU, 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.