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Home >> Honda >> 2011 >> Insight Base >> Repair and Diagnosis >> Hybrid/Electric Powertrain >> Electric Motor Systems >> IMA System >> DTC Troubleshooting >> DTC U0038 (99): IMA-CAN Malfunction (BUS-OFF (Motor Control Module (MCM))); DTC U1204 (55): IMA-CAN Malfunction (Powertrain Control Module (PCM) - Motor Control Module (MCM))
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DTC U0038 (99): IMA-CAN Malfunction (BUS-OFF (Motor Control Module (MCM))); DTC U1204 (55): IMA-CAN Malfunction (Powertrain Control Module (PCM) - Motor Control Module (MCM))

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).
  2. Clear the DTC with the HDS (see DTC CLEAR  ).
  3. Check the ECT SENSOR 1 in the IMA DATA LIST with the HDS.

    Is 419 °F (215 °C) indicated? 

    YES  -go to step 4.

    NO  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the PCM and the MCM.

  4. Jump the SCS line with the HDS.
  5. Turn the ignition switch to LOCK (0).
  6. Disconnect PCM connector A (44P).
  7. Measure the resistance between PCM connector terminals A38 and A39.
    Fig 1: Measuring Resistance Between PCM Connector Terminals A38 And A39
    G06429890Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 120 Ω? 

    YES  -go to step  19.

    NO  -

    • If there is no continuity, go to step  13.
    • If there is 1 Ω or less, go to step 8.
  8. Turn the battery module switch OFF (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  9. Remove the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ).
  10. Remove the PCU lid, the PCU busplate, and the PCU cover (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  11. Disconnect MCM connector A (31P).
  12. Check for continuity between MCM connector terminals A8 and A9.
    Fig 2: Checking Continuity Between MCM Connector Terminals A8 And A9
    G06429891Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the MCM connector terminals A8 and A9, then go to step  31.

    NO  -go to step  38.

  13. Turn the battery module switch OFF (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  14. Remove the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ).
  15. Remove the PCU lid, the PCU busplate, and the PCU cover (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  16. Disconnect MCM connector A (31P).
  17. Check for continuity between MCM connector terminal A8 and PCM connector terminal A38.
    Fig 3: Checking Continuity Between MCM Connector Terminal A8 And PCM Connector Terminal A38
    G00496911Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -go to step 18.

    NO  -Repair an open in the wire between the PCM (A38) and the MCM (A8), then go to step  31.

  18. Check for continuity between MCM connector terminal A9 and PCM connector terminal A39.
    Fig 4: Checking Continuity Between MCM Connector Terminal A9 And PCM Connector A39
    G06429893Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -go to step 38.

    NO  -Repair an open in the wire between the PCM (A39) and the MCM (A9), then go to step  31.

  19. Turn the battery module switch OFF (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR ).
  20. Remove the IPU cover (see IPU COVER REMOVAL/INSTALLATION ).
  21. Remove the PCU lid, the PCU busplate, and the PCU cover (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION ).
  22. Disconnect MCM connector A (31P).
  23. Check for continuity between MCM connector terminal A8 and body ground.
    Fig 5: Checking Continuity Between MCM Connector Terminal A8 And Body Ground
    G06429896Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire between the PCM (A38) and the MCM (A8), then go to step  31.

    NO  -go to step 24.

  24. Check for continuity between MCM connector terminal A9 and body ground.
    Fig 6: Checking Continuity Between MCM Connector Terminal A9 And Body Ground
    G06429895Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short to ground in the wire between the PCM (A39) and the MCM (A9), then go to step  31.

    NO  -Go to step 25.

  25. Turn the ignition switch to ON (II).
  26. Measure the voltage between MCM connector terminal A8 and body ground.
    Fig 7: Measuring Voltage Between MCM Connector Terminal A8 And Body Ground
    G06429898Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5-12 V? 

    YES  -Repair a short to power in the wire between the PCM (A38) and the MCM (A8), then go to step  31.

    NO  -go to step 27.

  27. Measure the voltage between MCM connector terminal A9 and body ground.
    Fig 8: Measuring Voltage Between MCM Connector Terminal A9 And Body Ground
    G06429899Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5-12 V? 

    YES  -Repair a short to power in the wire between the PCM (A39) and the MCM (A9), then go to step  31.

    NO  -go to step 28.

  28. Turn the ignition switch to LOCK (0).
  29. Reconnect PCM connector A (44P).
  30. Measure the resistance between MCM connector terminals A8 and A9.
    Fig 9: Measuring Resistance Between MCM Connector Terminals A8 And A9
    G06429900Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 120 Ω? 

    YES  -go to step  38.

    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 ), and recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ), then go to step 31.

  31. Reconnect all connectors.
  32. Reinstall the PCU cover, the PCU busplate, and the PCU lid (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  33. Reinstall the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ), then turn the battery module switch ON (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  34. Turn the ignition switch to ON (II).
  35. Clear the DTC with the HDS (see DTC CLEAR  ).
  36. Check for Pending or Confirmed DTCs in the IMA SYSTEM with the HDS.

    Is DTC U0038 (99) indicated? 

    YES  -Check for poor connections or loose terminals at the PCM and the MCM, then go to step  1.

    NO  -go to step 37.

  37. Monitor the OBD STATUS for DTC U0038 (99) in the DTCs MENU with the HDS.

    Does the screen indicate PASSED? 

    YES  -Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 36, go to the indicated DTC's troubleshooting.

    NO  -If the screen indicates FAILED, check for poor connections or loose terminals at the PCM and MCM, then go to step  1. If the screen indicates NOT COMPLETED, keep the ignition switch ON (II) until a result comes on.

  38. Reconnect all connectors.
  39. Reinstall the PCU cover, the PCU busplate, and the PCU lid (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  40. Reinstall the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ), then turn the battery module switch ON (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  41. Update the MCM if it does not have the latest software (see MOTOR CONTROL MODULE (MCM) UPDATE  ), or substitute a known-good MCM (see SUBSTITUTING THE MCM  ).
  42. Turn the ignition switch to ON (II).
  43. Check for Pending or Confirmed DTCs with the HDS in the IMA SYSTEM.

    Is DTC U0038 (99) indicated? 

    YES  -Check for poor connections or loose terminals at the PCM and the MCM. If the MCM was updated, substitute a known-good MCM (see SUBSTITUTING THE MCM  ), and recheck. If the MCM was substituted, go to step  1.

    NO  -go to step 44.

  44. Monitor the OBD STATUS for DTC U0038 (99) in the DTCs MENU with the HDS.

    Does the screen indicate PASSED? 

    YES  -If the MCM was updated, troubleshooting is complete. If the MCM was substituted, replace the original MCM (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ). If any other Pending or Confirmed DTCs were indicated in step 43, go to the indicated DTC's troubleshooting.

    NO  -If the screen indicates FAILED, check for poor connections or loose terminals at the PCM and the MCM. If the MCM was updated, substitute a known-good MCM (see SUBSTITUTING THE MCM  ), and recheck. If the MCM was substituted, go to step  1. If the screen indicates NOT COMPLETED, keep the ignition switch ON (II) until a result comes on.

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