Begin the system diagnosis by reviewing the Differential Carrier Assembly Disassembled Views , Differential Carrier Assembly Description and Locking Differential Description and Operation in Drive Axle - Locking/Limited Slip and Transfer Case Description and Operation in Transfer Case - Steyr Unit Repair. Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Rear Differential Carrier in order to identify the correct procedure for diagnosing the system and where the procedure is located.