DTC U1280: Communication Bus Line Error (BUS-OFF)
WARNING: This page is about a different car, the 2011 Honda Pilot, 2010 Honda Pilot, and 2009 Honda Pilot. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
If you are troubleshooting multiple DTCs, be sure to follow instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A
).
- Clear the DTCs with the HDS.
- Turn the ignition switch to LOCK (0) and then back to ON (II).
- Wait for 6 seconds or more.
- Check for DTCs with the HDS.
Is DTC U1280 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 battery condition (see BATTERY TEST ) and the charging system. ■
- 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.CONTROL UNIT CONNECTOR REFERENCE TABLE
Control Unit Connector Door multiplex control unit 37P connector Gauge control module 32P connector Immobilizer-keyless control unit 7P connector Audio unit(1) Connector D (20P) Climate control (2) unit Connector A (36P) HVAC control unit (3) unit Connector A (24P) Power tailgate control unit Connector C (14P) Automatic lighting control unit 14P connector Power seat control unit (4) Connector B (40P) Parking and back-up sensor control unit 16P connector HandsFreeLink control unit 28P connector (1) 6CD Type (2) With climate control system (3) Without climate control system (4) With DPMS Is DTC U1280 indicated with each individual unit disconnected?
YES - Go to step 7.
NO - Go to INPUT TEST for the control unit that was disconnected when DTC U1280 did not reset and perform all power and ground input tests. If the tests prove OK, replace that unit. ■
- See POWER WINDOW MASTER SWITCH INPUT TEST
- See GAUGE CONTROL MODULE INPUT TEST
- See IMMOBILIZER-KEYLESS CONTROL UNIT INPUT TEST
- Audio unit
- Climate control unit input test (see CLIMATE CONTROL UNIT POWER, GROUND, AND COMMUNICATION CIRCUIT TROUBLESHOOTING )
- HVAC control unit input test (see HVAC CONTROL POWER, GROUND, AND COMMUNICATION CIRCUIT TROUBLESHOOTING ).
- Power tailgate control unit input test (see CONTROL UNIT INPUT TEST/REPLACEMENT )
- Automatic lighting control unit input test (see AUTOMATIC LIGHTING CONTROL UNIT INPUT TEST/REPLACEMENT )
- Power seat control unit input test (see POWER MIRROR CONTROL UNIT INPUT TEST/REPLACEMENT )
- Parking and back-up sensor control unit input test (see PARKING AND BACK-UP SENSOR CONTROL UNIT INPUT TEST/REPLACEMENT )
- Turn the ignition switch to LOCK (0).
- Disconnect each control unit connector in the table below.CONTROL UNIT CONNECTOR REFERENCE TABLE
Control Unit Connector Door multiplex control unit 37P connector Gauge control module 32P connector Immobilizer-keyless control unit 7P connector Audio unit(1) Connector D (20P) Climate control unit(2) Connector A (36P) HVAC control unit(3) Connector A (24P) Power tailgate control unit Connector C (14P) Automatic lighting control unit 14P connector Power seat control unit (4) Connector B (40P) Parking and back-up sensor control unit 16P connector HandsFreeLink control unit 28P connector (1) 6CD type (2) With climate control system (3) Without climate control system (4) With DPMS - Disconnect under-dash fuse/relay box connector T (34P).
- Check for continuity between under-dash fuse/relay box connector T (34P) terminals No. 12 and No. 29.
Is there continuity?
YES - A short between the B-CAN wires. ■
NO - Go to step 11.
- Check for continuity between body ground and under-dash fuse/relay box connector T (34P) terminals No. 12 and No. 29 individually.
Is there continuity?
YES - A short to ground in the B-CAN wire(s). ■
NO - Faulty MICU, replace the under-dash fuse/relay box (see ).