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Home >> Acura >> 2009 >> TL Base >> Repair and Diagnosis (Single Page) >> Drivelines & Axles >> Differentials & Drive Axles >> Rear Differential >> DTC Troubleshooting >> DTC 91-1: SH-AWD Control Unit Programming Error
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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), or press the engine start/stop button to select the OFF mode while updating the SH-AWD system If you do, the SH-AWD system can be damaged
  1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
  2. Do the SH-AWD system update procedure (see HOW TO TROUBLESHOOT CIRCUITS AT THE SH-AWD CONTROL UNIT )
  3. Check for DTCs with the HDS

    Is DTC 91-1 indicated? 

    YES  -Substitute a known-good SH-AWD control unit (see SH-AWD CONTROL UNIT REPLACEMENT ), and recheck 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