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DTC 86: F-CAN Communication Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION  ).
  1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  2. Clear the DTC with the HDS.
  3. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  4. Start and run the engine for at least 5 seconds.
  5. Check for DTCs with the HDS.

    Is DTC 86 indicated? 

    YES  - Go to step 6.

    NO  - Check the COMMU FI ECU, COMMU A/T (A/T), COMMU GAUGE, COMMU YAW RATE/G, COMMU STEERING ANGLE S (With SH-AWD), and COMMU 4WD (With SH-AWD) in the VSA FREEZE DATA with the HDS. Then check for F-CAN communication lines continuity to the appropriate system or sensor and loose terminals in the appropriate system or sensor connectors.

  6. Check the COMMU Fl ECU, COMMU A/T (A/T), COMMU GAUGE, COMMU YAW RATE/G, COMMU STEERING ANGLE S (With SH-AWD), and COMMU 4WD (With SH-AWD) in the VSA DATA LIST with the HDS.

    Is there a communication error in the system or sensor? 

    YES  - Go to step 7.

    NO  - Go to step  24.

  7. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  8. Short the SCS line with the HDS.
  9. Disconnect ECM/PCM connector A (49P) (see ECM/PCM REPLACEMENT ).
  10. Disconnect the VSA modulator-control unit 47P connector (see step  5).
  11. Disconnect the gauge control module 32P connector (see GAUGE CONTROL MODULE REPLACEMENT ).
  12. Disconnect the yaw rate-acceleration sensor 4P connector (see YAW RATE-ACCELERATION SENSOR REPLACEMENT  ).
  13. With SH-AWD: Disconnect the steering angle sensor 5P connector (see STEERING ANGLE SENSOR REPLACEMENT  ).
  14. With SH-AWD: Disconnect SH-AWD control unit connector A (20P) (see REAR DIFFERENTIAL FLUID TEMPERATURE SENSOR REPLACEMENT ).
  15. Check the F-CAN communication lines for continuity between the VSA modulator-control unit and the appropriate system or sensor (see table below).
    Component F-CAN L Terminal F-CAN H Terminal
    VSA Modulator-Control Unit No. 13 No. 12
    ECM/PCM No. A49 No. A48
    Gauge Control Module No. 13 No. 14
    Yaw Rate-Acceleration Sensor No. 2 No. 3
    Steering Angle Sensor (With SH-AWD) No. 2 No. 4
    SH-AWD Control Unit (With SH-AWD) No. A20 No. A10
    Fig 1: Checking F-CAN Communication Lines For Continuity Between VSA Modulator-Control Unit And System Or Sensor
    G08067186Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Measuring Resistance Between VSA Modulator-Control Unit 47P And Gauge Control Module 32P Connector
    G08067187Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Measuring Resistance Between VSA Modulator-Control Unit 47P And Yaw Rate-Acceleration Sensor 4P Connector
    G08067188Courtesy of AMERICAN HONDA MOTOR CO., INC.

    With SH-AWD: 

    Fig 4: Measuring Resistance Between VSA Modulator-Control Unit 47P And Steering Angle Sensor 5P Connector (With SH-AWD)
    G08067189Courtesy of AMERICAN HONDA MOTOR CO., INC.

    With SH-AWD: 

    Fig 5: Measuring Resistance Between VSA Modulator-Control Unit 47P And SH-AWD Control Unit A (20P) Connector (With SH-AWD)
    G08067190Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity on the F-CAN communication lines? 

    YES  -

    • If the appropriate system or sensor is the yaw rate-acceleration sensor: Go to step 16.
    • If the appropriate system or sensor is not the yaw rate-acceleration sensor: Go to step  20.

    NO  - Repair an open in the appropriate wire.

  16. Check for loose terminals in the yaw rate-acceleration sensor 4P connector.

    Is the yaw rate-acceleration sensor 4P connector OK? 

    YES  - Go to step 17.

    NO  - Repair or reconnect the connector securely.

  17. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
  18. Measure the voltage between yaw rate-acceleration sensor 4P connector terminals No. 1 and No. 4.
    Fig 6: Measuring Voltage Between Yaw Rate-Acceleration Sensor 4P Connector Terminals No. 1 And No. 4
    G08067191Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Replace the yaw rate-acceleration sensor (see YAW RATE-ACCELERATION SENSOR REPLACEMENT  ).

    NO  - Go to step 19.

  19. Measure the voltage between yaw rate-acceleration sensor 4P connector terminal No. 1 and body ground.
    Fig 7: Measuring Voltage Between Yaw Rate-Acceleration Sensor 4P Connector Terminal No. 1 And Body Ground
    G08067192Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Repair an open in the wire between the yaw rate-acceleration sensor and body ground (G403).

    NO  - Repair an open in the wire between the yaw rate-acceleration sensor and the driver's under-dash fuse/relay box.

  20. Check for loose terminals in the appropriate system connectors.

    Are the appropriate system connectors OK? 

    YES  - Go to step 21.

    NO  - Repair or reconnect the connector securely.

  21. Reconnect all connectors.
  22. Start and run the engine for at least 5 seconds.
  23. Check for other system DTCs with the HDS.

    Is another DTCs indicated? 

    YES  - Do the appropriate DTC troubleshooting.

    NO  - Go to step 24.

  24. Update the VSA modulator-control unit if it does not have the latest software (see VSA MODULATOR-CONTROL UNIT UPDATE  ).
  25. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  26. Start and run the engine for at least 5 seconds.
  27. Check for DTCs with the HDS.

    Is DTC 86 indicated? 

    YES  - Check for loose terminals in the VSA modulator-control unit 47P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION  ).

    NO  - If the VSA modulator-control unit was updated, troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCS TROUBLESHOOTING .

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