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F-CAN Circuit Troubleshooting

  1. Turn the ignition switch to LOCK (0).
  2. Jump the SCS line with the HDS.
  3. Disconnect PCM connector A (49P).
  4. Measure the resistance between PCM connector terminals A48 and A49, then compare your reading to the model/trim level listed the table below.
    VEHICLES WITH ACTIVE DAMPER

    Other Systems Resistance
    Adaptive cruise control (ACC) (USA model) About 44-55 Ω
    Adaptive cruise control (ACC) (Canada model) About 45-56 Ω
    VEHICLES WITHOUT ACTIVE DAMPER

    Other Systems Resistance
    Adaptive cruise control (ACC) (USA model) About 46-57 Ω
    Adaptive cruise control (ACC) (Canada model) About 46-57 Ω
    Without adaptive cruise control (ACC) About 48-59 Ω
    Fig 1: Measuring Resistance Between PCM Connector Terminals A48 And A49
    G08057129Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is the resistance OK? 

    YES  -Go to step  20.

    NO  -Go to step 5.

  5. Disconnect these connectors:
  6. Check for continuity between PCM connector terminals A48 and A49.
    Fig 2: Checking Continuity Between PCM Connector Terminals A48 And A49
    G08057130Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wires between PCM connector terminals A48 and A49.

    NO  -Go to step 7.

  7. Check for continuity between PCM connector terminal A48 and gauge control module connector A (12P) terminal No. 12.
    Fig 3: Checking Continuity Between PCM Connector Terminal A48 And Gauge Control Module Connector A (12P) Terminal No. 12
    G08057131Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 8.

    NO  -Repair an open in the wire between the PCM (A48) and the gauge control module.

  8. Check for continuity between PCM connector terminal A48 and VSA modulator-control unit 46P connector terminal No. 39.
    Fig 4: Checking Continuity Between PCM Connector Terminal A48 And VSA Modulator-Control Unit 46P Connector Terminal No. 39
    G08057132Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 9.

    NO  -Repair an open in the wire between the PCM (A48) and the VSA modulator-control unit.

  9. Check for continuity between PCM connector terminal A48 and SH-AWD control unit connector A (20P) terminal No. 10.
    Fig 5: Checking Continuity Between PCM Connector Terminal A48 And SH-AWD Control Unit Connector A (20P) Terminal No. 10
    G08057133Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -

    • With ACC: Go to step 10.
    • Without ACC: Go to step  11.

    NO  -Repair an open in the wire between the PCM (A48) and the SH-AWD control unit.

  10. Check for continuity between PCM connector terminal A48 and ACC unit 20P connector terminal No. 10.
    Fig 6: Checking Continuity Between PCM Connector Terminal A48 And ACC Unit 20P Connector Terminal No. 10
    G08057134Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 11.

    NO  -Repair an open in the wire between the PCM (A48) and the ACC unit.

  11. Check for continuity between PCM connector terminal A49 and gauge control module connector A (12P) terminal No. 6.
    Fig 7: Checking Continuity Between PCM Connector Terminal A49 And Gauge Control Module Connector A (12P) Terminal No. 6
    G08057135Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 12.

    NO  -Repair an open in the wire between the PCM (A49) and the gauge control module.

  12. Check for continuity between PCM connector terminal A49 and VSA modulator-control unit 46P connector terminal No. 38.
    Fig 8: Checking Continuity Between PCM Connector Terminal A49 And VSA Modulator-Control Unit 46P Connector Terminal No. 38
    G08057136Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 13.

    NO  -Repair an open in the wire between the PCM (A49) and the VSA modulator-control unit.

  13. Check for continuity between PCM connector terminal A49 and SH-AWD control unit connector A (20P) terminal No. 20.
    Fig 9: Checking Continuity Between PCM Connector Terminal A49 And SH-AWD Control Unit Connector A (20P) Terminal No. 20
    G08057137Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -

    • With ACC: Go to step 14.
    • Without ACC: Go to step  15.

    NO  -Repair an open in the wire between the PCM (A49) and the SH-AWD control unit.

  14. Check for continuity between PCM connector terminal A49 and ACC unit 20P connector terminal No. 20.
    Fig 10: Checking Continuity Between PCM Connector Terminal A49 And ACC Unit 20P Connector Terminal No. 20
    G08057138Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 15.

    NO  -Repair an open in the wire between the PCM (A49) and the ACC unit.

  15. Reconnect the VSA modulator-control unit 46P connector.
  16. Measure the resistance between PCM connector terminals A48 and A49.
    Fig 11: Measuring Resistance Between PCM Connector Terminals A48 And A49
    G08057139Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 108-132 Ω? 

    YES  -Go to step 17.

    NO  -Substitute a known-good VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).

  17. Disconnect the VSA modulator-control unit 46P connector.
  18. Reconnect SH-AWD control unit connector A (20P).
  19. Measure the resistance between PCM connector terminals A48 and A49.
    Fig 12: Measuring Resistance Between PCM Connector Terminals A48 And A49
    G08057140Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 108-132 Ω? 

    YES  -Go to step 20.

    NO  -Substitute a known-good SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT ), then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT ).

  20. Disconnect these connectors:
  21. Check for continuity between PCM connector terminal A48 and body ground.
    Fig 13: Checking Continuity Between PCM Connector Terminal A48 And Body Ground
    G08057141Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A48) and the gauge control module, the VSA modulator-control unit, the SRS unit, the TPMS control unit, the yaw rate-lateral/longitudinal acceleration sensor, the steering angle sensor, the SH-AWD control unit, the active damper control unit (with active damper), the AcuraLink control unit (with AcuraLink), the ACC unit (with ACC), the E-pretensioner unit (with ACC), or the DLC.

    NO  -Go to step 22.

  22. Check for continuity between PCM connector terminal A49 and body ground.
    Fig 14: Checking Continuity Between PCM Connector Terminal A49 And Body Ground
    G08057142Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the PCM (A49) and the gauge control module, the VSA modulator-control unit, the SRS unit, the TPMS control unit, the yaw rate-lateral/longitudinal acceleration sensor, the steering angle sensor, the SH-AWD control unit, the active damper control unit (with active damper), the AcuraLink control unit (with AcuraLink), the ACC unit (with ACC), the E-pretensioner unit (ACC), or the DLC.

    NO  -Go to step 23.

  23. Reconnect all connectors.
  24. Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
  25. Disconnect gauge control module connector A (12P).
  26. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).

    NO  -Go to step 27.

  27. Turn the ignition switch to LOCK (0).
  28. Reconnect gauge control module connector A (12P).
  29. Disconnect the VSA modulator-control unit 46P connector.
  30. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).

    NO  -Go to step 31.

  31. Turn the ignition switch to LOCK (0).
  32. Reconnect the VSA modulator-control unit 46P connector.
  33. Disconnect SRS unit connector A (39P).
  34. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the SRS unit (see SRS UNIT REPLACEMENT ).

    NO  -Go to step 35.

  35. Turn the ignition switch to LOCK (0).
  36. Reconnect SRS unit connector A (39P).
  37. Disconnect the TPMS control unit 20P connector.
  38. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace TPMS control unit (see TPMS CONTROL UNIT REPLACEMENT ).

    NO  -Go to step 39.

  39. Turn the ignition switch to LOCK (0).
  40. Reconnect the TPMS control unit 20P connector.
  41. Disconnect the yaw rate-lateral/longitudinal acceleration sensor 4P connector.
  42. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the yaw rate-lateral/longitudinal acceleration sensor (see YAW RATE-LATERAL/LONGITUDINAL ACCELERATION SENSOR REPLACEMENT ).

    NO  -Go to step 43.

  43. Turn the ignition switch to LOCK (0).
  44. Reconnect the yaw rate-lateral/longitudinal acceleration sensor 4P connector.
  45. Disconnect the steering angle sensor 5P connector.
  46. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the steering angle sensor (see STEERING ANGLE SENSOR REPLACEMENT ).

    NO  -

    • With active damper: Go to step 47.
    • Without active damper: Go to step  51.
  47. Turn the ignition switch to LOCK (0).
  48. Reconnect the steering angle sensor 5P connector.
  49. Disconnect active damper control unit connector B (14P).
  50. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the active damper control unit (see ACTIVE DAMPER CONTROL UNIT REPLACEMENT ).

    NO  -Go to step 51.

  51. Turn the ignition switch to LOCK 0).
  52. Reconnect the steering angle sensor 5P connector or active damper control unit connector B (14P).
  53. Disconnect SH-AWD control unit connector A (20P)
  54. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT ).

    NO  -

    • With ACC: Go to step 55.
    • Without ACC: Update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).
  55. Turn the ignition switch to LOCK (0).
  56. Reconnect SH-AWD control unit connector A (20P).
  57. Disconnect the ACC unit 20P connector.
  58. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the ACC unit (see ADAPTIVE CRUISE CONTROL (ACC) UNIT REMOVAL/INSTALLATION ).

    NO  -Go to step 59.

  59. Turn the ignition switch to LOCK (0).
  60. Reconnect the ACC unit 20P connector.
  61. Disconnect E-pretensioner unit connector B (14P).
  62. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the E-pretensioner unit (see E-PRETENSIONER UNIT REPLACEMENT ).

    NO  -

    • With AcuraLink: Go to step 63.
    • Without AcuraLink: Update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).
  63. Turn the ignition switch to LOCK (0).
  64. Reconnect E-pretensioner unit connector B (14P).
  65. Disconnect AcuraLink control unit connector A (32P).
  66. Turn the ignition switch to ON (II), and read the HDS.

    Does the HDS identify the vehicle? 

    YES  -Replace the AcuraLink control unit (see ACURALINK CONTROL UNIT (XM RECEIVER) REMOVAL/INSTALLATION ).

    NO  -Update the PCM if it does not have the latest software (see PCM UPDATE  ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM (see PCM REPLACEMENT  ).

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