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DTC 91-1: SH-AWD Control Unit Programming Error

NOTE:
  • Before you troubleshoot, review the general troubleshooting information (see GENERAL TROUBLESHOOTING INFORMATION  ).
  • DTC 91-1 is stored when the SH-AWD system update is not completed.
  • Do not turn the ignition switch to LOCK (0) while updating the SH-AWD system. If you do, the SH-AWD system can be damaged.
  1. Turn the ignition switch to ON (II).
  2. Do the SH-AWD system update procedure (see SH-AWD® CONTROL UNIT UPDATE  ).
  3. Check for DTCs with the HDS.

    Is DTC 91-1 indicated? 

    YES  -Update the SH-AWD control unit if it does not have the latest software (see SH-AWD® CONTROL UNIT UPDATE  ), or substitute a known-good SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT  ), and recheck. If the symptom/indication goes away with the updated SH-AWD control unit, troubleshooting is complete. If the symptom/indication goes away with a known-good SH-AWD control unit, replace the original SH-AWD control unit (see SH-AWD® CONTROL UNIT REPLACEMENT  ).

    NO  -Update is complete.