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DTC P0A1B (84): Motor Control Module (MCM) Internal 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. Turn the ignition switch to LOCK (0), and wait 1 minute.
  4. Turn the ignition switch to ON (II).
  5. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0A1B (84) indicated? 

    YES  -go to step 6.

    NO  -Intermittent failure, the system is OK at this time.

  6. 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  ).
  7. Turn the ignition switch to LOCK (0), and wait 1 minute.
  8. Turn the ignition switch to ON (II).
  9. Check for Pending or Confirmed DTCs with the HDS.

    Is DTC P0A1B (84) indicated? 

    YES  -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 10.

  10. Monitor the OBD STATUS for DTC P0A1B (84) 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 9, go to the indicated DTC's troubleshooting.

    NO  -

    • If the screen indicates FAILED: 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.