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DTC P1634 (47): Motor Power Inverter (MPI) Module Signal Circuit Malfunction

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
  • Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION  ).
  • If the DTC cannot be cleared, do the troubleshooting for DTC U1204 (55).
  1. Turn the ignition switch to ON (II).
  2. Clear the DTC with the HDS (see DTC CLEAR  ).
  3. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1634 (47) 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 MCM and the MPI module.

  4. Do the IPU MODULE FAN DRIVE in the INSPECTION MENU with the HDS.

    Does the screen indicate OUT OF RANGE? 

    YES  -go to step 5.

    NO  -If the screen indicates CONDITION IS NORMAL, go to step  15.

  5. Check the No. 53 + B IMA 2 (10 A) fuse in the under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -go to step 6.

    NO  -Repair a short to ground in the wire between the IPU module fan or the MPI module and the No. 53 +B IMA 2 (10 A) fuse. Also replace the No. 53 +B IMA 2 (10 A) fuse, then go to step  40.

  6. Turn the ignition switch to LOCK (0).
  7. Turn the battery module switch OFF (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  8. Remove the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ).
  9. Turn the ignition switch to ON (II), and listen for a clicking sound from MCM relay 2 (A).
    Fig 1: Identifying MCM Relay 2
    G06429874Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there a clicking sound? 

    YES  -go to step 10.

    NO  -go to step  27.

  10. Turn the ignition switch to LOCK (0).
  11. Remove MCM relay 2.
  12. Check MCM relay 2 (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -go to step 13.

    NO  -Replace MCM relay 2, then go to step  33.

  13. Turn the ignition switch to ON (II).
  14. Measure the voltage between MCM relay 2 4P connector terminal No. 2 and body ground.
    Fig 2: Measuring Voltage Between MCM Relay 2 4P Connector Terminal 2 And Body Ground
    G06429875Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Repair an open in the wire between MCM relay 2 and the MPI module 12P connector terminal No. 12, then go to step  33.

    NO  -Repair an open in the wire between the No. 53 + B IMA 2 (10 A) fuse and MCM relay 2, then go to step  33.

  15. Turn the ignition switch to LOCK (0).
  16. Turn the battery module switch OFF (see DISCONNECTING THE MOTOR POWER CABLE CONNECTOR FROM THE MOTOR STATOR  ).
  17. Remove the IPU cover (see IPU COVER REMOVAL/INSTALLATION  ).
  18. Remove the PCU lid, the PCU busplate, and the PCU cover (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  19. Disconnect MCM connector C (22P).
  20. Measure the resistance between MCM connector terminal C20 and body ground.
    Fig 3: Measuring Resistance Between MCM Connector Terminal C20 And Body Ground
    G06429876Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there 1 MΩ or more? 

    YES  -go to step 21.

    NO  -go to step  37.

  21. Disconnect the MPI module 12P connector (A).
    Fig 4: Identifying MPI Module 12P Connector
    G06429877Courtesy of AMERICAN HONDA MOTOR CO., INC.
  22. Reconnect MCM connector C (22P).
  23. Turn the ignition switch to ON (II).
  24. Measure the voltage between MPI module 12P connector terminals No. 7 and No. 12.
    Fig 5: Measuring Voltage Between MPI Module 12P Connector Terminals 7 And 12
    G00496909Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -go to step 25.

    NO  -go to step  39.

  25. Measure the voltage between MPI module 12P connector terminal No. 5 and body ground.
    Fig 6: Measuring Voltage Between MPI Module 12P Connector Terminal 5 And Body Ground
    G06429879Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 5 V? 

    YES  -Replace the MPI module (see MOTOR POWER INVERTER (MPI) MODULE REMOVAL/INSTALLATION  ), then go to step  33.

    NO  -go to step 26.

  26. Measure the voltage between MCM connector terminal C20 and body ground.
    Fig 7: Measuring Voltage Between MCM Connector Terminal C20 And Body Ground
    G06429880Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there about 12 V? 

    YES  -Repair an open in the wire between the MPI module 12P connector and the MCM (C20), then go to step  33.

    NO  -go to step  47.

  27. Turn the ignition switch to LOCK (0).
  28. Remove MCM relay 2.
  29. Check MCM relay 2 (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -go to step 30.

    NO  -Replace MCM relay 2, then go to step  33.

  30. Turn the ignition switch to ON (II).
  31. Measure the voltage between MCM relay 2 4P connector terminal No. 4 and body ground.
    Fig 8: Measuring Voltage Between MCM Relay 2 4P Connector Terminal 4 And Body Ground
    G06429881Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -go to step 32.

    NO  -Repair an open in the wire between MCM relay 1 and MCM relay 2, then go to step  33.

  32. Turn the ignition switch to LOCK (0).
  33. Reinstall MCM relay 2 (A).
    Fig 9: Identifying MCM Relay 2
    G06429882Courtesy of AMERICAN HONDA MOTOR CO., INC.
  34. Remove the PCU lid, the PCU busplate, and the PCU cover (see Motor Control Module (MCM) Removal/Installation ).
  35. Turn the ignition switch to ON (II).
  36. Measure the voltage between MCM connector terminal A6 and body ground.
    Fig 10: Measuring Voltage Between MCM Connector Terminal A6 And Body Ground
    G06429883Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -go to step  47.

    NO  -Repair an open in the wire between MCM relay 2 and the MCM (A6), then go to step  40.

  37. Disconnect the MPI module 12P connector (A).
    Fig 11: Identifying MPI Module 12P Connector
    G06429884Courtesy of AMERICAN HONDA MOTOR CO., INC.
  38. Check for continuity between MCM connector terminal C20 and body ground.
    Fig 12: Checking Continuity Between MCM Connector Terminal C20 And Body Ground
    G06429885Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the MPI module 12P connector and the MCM (C20), then go to step  40.

    NO  -Replace the MPI module (see MOTOR POWER INVERTER (MPI) MODULE REMOVAL/INSTALLATION  ), then go to step  40.

  39. Measure the voltage between MPI module 12P connector terminal No. 12 and body ground.
    Fig 13: Measuring Voltage Between MPI Module 12P Connector Terminal 12 And Body Ground
    G00496908Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Repair an open in the wire between the MPI module 12P connector terminal No. 7 and G901, then go to step 40.

    NO  -Repair an open in the wire between MCM relay 2 and the MPI module 12P connector terminal No. 12, then go to step 40.

  40. Reconnect all connectors.
  41. If removed, reinstall the PCU cover, the PCU busplate, and the PCU lid (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  42. If removed, 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  ).
  43. Turn the ignition switch to ON (II).
  44. Clear the DTC with the HDS (see DTC CLEAR  ).
  45. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1634 (47) indicated? 

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

    NO  -go to step 46.

  46. Monitor the OBD STATUS for DTC P1634 (47) 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 45, go to the indicated DTC's troubleshooting.

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

  47. Reconnect all connectors.
  48. Reinstall the PCU cover, the PCU busplate, and the PCU lid (see MOTOR CONTROL MODULE (MCM) REMOVAL/INSTALLATION  ).
  49. 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  ).
  50. 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  ).
  51. Turn the ignition switch to ON (II).
  52. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P1634 (47) indicated? 

    YES  -Check for poor connections or loose terminals at the MCM and the MPI module. 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 53.

  53. Monitor the OBD STATUS for DTC P1634 (47) 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 52, go to the indicated DTC's troubleshooting.

    NO  -If the screen indicates FAILED, check for poor connections or loose terminals at the MCM and the MPI module. 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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