DTC 86-12, 86-13: F-CAN Communication (2016-18)

2015 Acura RDX AWDSECTION DTC 86-12, 86-13: F-CAN Communication (2016-18)

DTC 86-12  : F-CAN Communication With ECM/PCM (PGM-FI) Malfunction DTC 86-13  : F-CAN Communication With PCM (AT/CVT) Malfunction

DTC Description DTC Freeze Frame
86-12 F-CAN Communication With ECM/PCM (PGM-FI) Malfunction    
86-13 F-CAN Communication With PCM (AT/CVT) Malfunction    

DTCs (VSA)

  1. DTC check:

    Press the engine start/stop button to select the ON mode.

    - 2. Clear the DTC with the HDS.

    Clear DTCs

    - 3. Press the engine start/stop button to select the OFF mode.

    - 4. Start the engine and let it idle for at least 5 seconds.

    - 5. Check for DTCs with the HDS.

    DTC Description DTC Freeze Frame
    86-11 F-CAN Bus-Off Malfunction    
    DTC Description DTC Freeze Frame
    86-12 F-CAN Communication With ECM/PCM (PGM-FI) Malfunction    
    86-13 F-CAN Communication With PCM (AT/CVT) Malfunction    

    Is DTC 86-12 or 86-13 indicated?

    YES 

    If only DTC 86-12 or 86-13 are indicated, go to step 2.

    YES 

    If DTC 86-11 is also indicated, go to DTC 86-11 .

    NO 

    Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.

  2. Open wire check (F CAN-L, F CAN-H lines):

    Press the engine start/stop button to select the OFF mode.

    - 2. Short the SCS line with the HDS.

    SCS Short

    - 3. Disconnect the following connectors.

    VSA modulator-control unit 38P connector
    PCM connector A (49P) - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2013-15), or How to Troubleshoot the A/T System (2013-15)

    - 4. Check for continuity between test points 1 and 2.

    Test condition OFF mode
      VSA modulator-control unit 38P connector: disconnected
      PCM connector A (49P): disconnected
    Test circuit F CAN-L
    Test point 1 VSA modulator-control unit 38P connector No. 26 (RED)
    Test point 2 PCM connector A (49P) No. 20 (RED)
    Test circuit F CAN-H
    Test point 1 VSA modulator-control unit 38P connector No. 38 (WHT)
    Test point 2 PCM connector A (49P) No. 19 (WHT)
    GHH78824Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The F CAN-L and F CAN-H wires are OK. Go to step 3.

    NO 

    Repair an open in the wire between the PCM and the VSA modulator-control unit.

  3. PCM check (update or substitution):

    Reconnect the following connectors.

    VSA modulator-control unit 38P connector
    PCM connector A (49P) - Refer to: How to Troubleshoot the Fuel and Emissions Systems (2013-15), or How to Troubleshoot the A/T System (2013-15)

    - 2. Update the PCM if it does not have the latest software , or substitute a known-good PCM .

    - 3. Clear the DTC with the HDS.

    Clear DTCs

    - 4. Press the engine start/stop button to select the OFF mode.

    - 5. Start the engine and let it idle for at least 5 seconds.

    - 6. Check for DTCs with the HDS.

    DTC Description DTC Freeze Frame
    86-12 F-CAN Communication With ECM/PCM (PGM-FI) Malfunction    
    86-13 F-CAN Communication With PCM (AT/CVT) Malfunction    

    Is DTC 86-12 or 86-13 indicated?

    YES 

    Go to step 4.

    NO 

    If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM .

  4. VSA modulator-control unit check (update):

    Update the VSA modulator-control unit if it does not have the latest software .

    - 2. Press the engine start/stop button to select the OFF mode.

    - 3. Start the engine and let it idle for at least 5 seconds.

    - 4. Check for DTCs with the HDS.

    DTC Description DTC Freeze Frame
         

    Is DTC 86-12 or 86-13 indicated?

    YES 

    Check for loose terminals in the VSA modulator-control unit 38P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit .

    NO 

    Troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.