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Tahoe / Yukon Service Manual

DTC C05FF or C15AC (1)

DTC C05FF or C15AC Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions DTC Descriptor DTC C05FF Range Actuator Position Not Learned DTC C15AC Transfer Case Range Actuator Learn Failed Symptom Byte Information: Symptom Byte List Circuit/System Description For an overview of the component/system, refer to: Transfer Case Description and Operation Conditions for Running the DTC Ignition = On System Voltage = 9 to 17.5 V Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC DTC C05FF 54 Range Actuator Position = Not Learned DTC C15AC 55 Range Actuator Position = Learn Failed Actions Taken When the DTC Sets Shifting = Disabled Driver Information Display = Service 4WD Electronic Park Brake will engage when the transmission is in Park Conditions for Clearing the DTC The conditions for setting the DTC no longer exist. A history DTC will clear after 40 consecutive malfunction-free ignition cycles. Reference Information Schematic Reference Transfer Case Control Schematics Connector End View Reference Master Electrical Component List Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References Circuit/System Verification

  1. Ignition » On / Vehicle » In Service Mode
  2. Verify there are no other DTCs set, except for DTC C05FF and/or C15AC. ⇒ If any other DTCs are set Diagnose other DTCs first. Refer to: Diagnostic Trouble Code (DTC) List - Vehicle. ⇓ If no other DTCs are set
  3. Verify DTC C05FF and/or C15AC is not set. ⇒ If the DTC is set 3.1. Perform the following learn procedure: Transfer Case Range Actuator Learn 3.2. Clear DTCs. 3.3. Ignition/Vehicle » Off 3.4. Disconnect the data link connector. 3.5. Wait 30 s before proceeding to the next step. 3.6. Ignition » On / Vehicle » In Service Mode 3.7. Verify the procedure was successful. ⇒ If the procedure was successful All OK. ⇓ If the procedure was not successful 3.8. Test or replace the component: A16 Transfer Case Four Wheel Drive Actuator ⇓ If the DTC is not set
  4. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Transfer Case Two/Four Wheel Drive Actuator Replacement — A16 Transfer Case Four Wheel Drive Actuator