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Tahoe / Yukon Service Manual

DTC C11B3 or C15A9

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 C11B3 Range Actuator Position Sensor and Transfer Case Range Position Sensor Correlation at Startup DTC C15A9 Range Actuator Position Sensor and Transfer Case Range Position Sensor Correlation at Runtime Symptom Byte Information: Symptom Byte List. Typical Scan Tool Data

Parameter 2WD Automatic 4WD High/Locke 4WD Low d Neutral
Range Actuator Position Sensor -10 to 25° 25 to 175° 25 to 175° -48 to -175° -20 to -48°
Transfer Case Range Position Sensor -10 to 25° 25 to 175° 25 to 175° -48 to -175° -20 to -48°

Circuit/System Description For an overview of the component/system, refer to: Transfer Case Description and Operation Conditions for Running the DTC System Voltage = 9 to 17.5 V DTC C05FB, C11AD, C11B9, C15AA, C15AB, C15C1 = Not set Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC Variation Between Transfer Case Range Position Sensor and Range Actuator Position Sensor = Greater than 7° Actions Taken When the DTC Sets Shifting = Disabled — Until vehicle is driven above 5 MPH for more than 30 seconds Shifting between 2WD High, 4WD/AWD Automatic, and 4WD High available after the vehicle is driven to enable shifting 4WD/AWD Automatic = Reduced Performance Electronic Park Brake will engage when the transmission is in Park Driver Information Display = Service 4WD Conditions for Clearing the DTC The conditions for setting the DTC no longer exist. Perform the scan tool configuration/reset function: Range Actuator Correlation Learn A history DTC will clear after 40 consecutive malfunction-free ignition cycles. Diagnostic Aids DTC C11B3 will set Range Actuator Position Sensor — Stored Value ≠ Current Value @ Ignition » On / Vehicle » In Service Mode Transfer Case Range Position Sensor — Stored Value ≠ Current Value @ Ignition » On / Vehicle » In Service Mode 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 no other DTC’s are set, except for DTC C05DD ⇒ If any other DTCs are set Refer to: Diagnostic Trouble Code (DTC) List - Vehicle. ⇓ If no other DTCs are set
  3. Perform the scan tool configuration/reset function: Range Actuator Correlation Learn
  4. Wait 10 s before proceeding to the next step.
  5. Ignition/Vehicle » Off
  6. Wait 30 s before proceeding to the next step.
  7. Ignition » On / Vehicle » In Service Mode
  8. Verify DTC C11B3, C15A9 is not set. ⇒ If the DTC is set Refer to: Circuit/System Testing ⇓ If the DTC is not set
  9. Operate the component: S126 Ride Control Switch» 2WD /4WD/AWD Automatic /4WD High/Locked /4WD Low Verify the DTC does not set. ⇒ If the DTC sets Refer to: Circuit/System Testing ⇓ If the DTC is not set
  10. All OK. Circuit/System Testing
  11. Ignition » On / Vehicle » In Service Mode
  12. Transfer Case Select Switch = 2WD
  13. Ignition/Vehicle » Off
  14. Remove the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor
  15. Verify a condition does not exist with the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor— Clean and inspect all mating surfaces. ⇒ If a condition exists Replace the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor ⇓ If no condition exists
  16. Rotate the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor— Position 2WD
  17. Connect the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor
  18. Ignition » On / Vehicle » In Service Mode
  19. Verify the scan tool parameter: Transfer Case Range Position Sensor = -10 to 25° ⇒ If not the specified state Replace the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor ⇓ If the specified state
  20. Rotate the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor— Position 4WD LOW
  21. Verify the scan tool parameter: Transfer Case Range Position Sensor = -48 to -175° ⇒ If not the specified state Replace the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor ⇓ If the specified state
  22. Rotate the component: Transfer Case Control Actuator Shaft Verify a condition does not exist with the component: Transfer Case Control Actuator Shaft — Rotate(s) ⇒ If a condition exists Mechanical Malfunction — Refer to: Transfer Case Disassemble ⇓ If no condition exists
  23. Ignition/Vehicle » Off
  24. Install the component: B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor
  25. Mark the installation position. — A16 Transfer Case Four Wheel Drive Actuator
  26. Remove the component: A16 Transfer Case Four Wheel Drive Actuator
  27. Ignition » On / Vehicle » In Service Mode
  28. Perform each scan tool control function: Range Actuator — Clockwise
  29. Verify the scan tool parameter: Range Actuator Position Sensor = 25 to 175° ⇒ If not the specified state Replace the component: A16 Transfer Case Four Wheel Drive Actuator ⇓ If the specified state
  30. Perform each scan tool control function: Range Actuator — Counterclockwise
  31. Verify the scan tool parameter: Range Actuator Position Sensor = -48 to -175° ⇒ If not the specified state Replace the component: A16 Transfer Case Four Wheel Drive Actuator ⇓ If the specified state
  32. Ignition/Vehicle » Off
  33. Install the component: A16 Transfer Case Four Wheel Drive Actuator
  34. Ignition » On / Vehicle » In Service Mode
  35. Perform the scan tool configuration/reset function: Range Actuator Correlation Learn
  36. Wait 10 s before proceeding to the next step.
  37. Ignition/Vehicle » Off
  38. Wait 30 s before proceeding to the next step.
  39. Ignition » On / Vehicle » In Service Mode
  40. Verify DTC C11B3, C15A9 is not set. ⇒ If the DTC is set Replace the component: K69 Transfer Case Control Module ⇓ If the DTC is not set
  41. 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 Transfer Case Two/Four Wheel Drive Actuator Position Sensor Replacement — B139 Transfer Case Two/Four Wheel Drive Actuator Position Sensor For control module replacement, programming, and setup refer to: Control Module References