Begin the system diagnosis by reviewing the Transfer Case Disassembled View in Transfer Case-Steyr Unit Repair and the Transfer Case Description and Operation , and the Differential Carrier Assembly Description in Rear Drive Axle. 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 - Transfer Case in order to identify the correct procedure for diagnosing the system and where the procedure is located.