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DTC U1280 (Body Control Module)

DTC U1280  : B-CAN 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 .

DTC Description DTC
U1280 B-CAN communication bus line error (BUS-OFF)  

DTC (Body Control Module)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Wait for at least 6 seconds.

    -4. Check for DTCs with the HDS.

    DTC Description DTC
    U1280 B-CAN communication bus line error (BUS-OFF)  

    Is DTC U1280 indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for loose or poor connections.

  2. B-CAN related units check

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the appropriate connector at each control unit in the chart one at a time. Clear the DTC, then recheck for DTCs after each unit is disconnected.

    Control Unit Connector
    Gauge control module Connector A (32P)
    Climate control unit / HVAC control unit Connector A (32P)
    Immobilizer-keyless control unit 7P connector
    Power window master switch 37P connector
    Automatic lighting control unit-sensor 5P connector
    Audio unit / Audio-navigation unit Connector A (24P)
    Front seat heater control unit 24P connector
    Power seat control unit Connector A (20P)
    Power tailgate control unit Connector A (24P)
    Relay control module Connector A (6P)
    Parking and back-up sensor control unit 16P connector
    Wireless charger 7P connector
    Left BSI radar unit 6P connector
    Right BSI radar unit 6P connector
    DTC Description DTC
    U1280 B-CAN communication bus line error (BUS-OFF)  

    Is DTC U1280 indicated with each individual unit disconnected?

    YES 

    Leave the connectors disconnected, and go to step 3.

    NO 

    Replace the control unit that was disconnected when DTC U1280 did not reset.

  3. Shorted wire check (B-CAN lines)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    Body control module connector B (36P)

    -3. Measure the resistance between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode Body control module connector B (36P): disconnected
    Test point 1 Body control module connector B (36P) No. 20
    Test point 2 Body ground
    Test point 1 Body control module connector B (36P) No. 21
    Test point 2 Body ground

    Is there 1.0 MΩ or more?

    YES 

    Go to step 4.

    NO 

    Repair a short to ground in the B-CAN wires.

  4. Shorted wire check (B-CAN_L to B-CAN_H line)

    -1. Measure the resistance between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode Body control module connector B (36P): disconnected
    Test point 1 Body control module connector B (36P) No. 20
    Test point 2 Body control module connector B (36P) No. 21

    Is there 1.0 MΩ or more?

    YES 

    The B-CAN_L to B-CAN_H wire is OK. Replace the body control module .

    NO 

    Repair a short in the B-CAN_L to B-CAN_H wire.