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Tahoe / Yukon Service Manual

DTC C05FB, C11B9, C15AB, or C15C1

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 C05FB Incremental Encoder Impulse Signal DTC C11B9 Incremental Encoder Direction Signal DTC C15AB Incremental Encoder Sensor Voltage Reference DTC C15C1 Incremental Encoder Sensor Low Reference Symptom Byte Information: Symptom Byte List Diagnostic Fault Information

Circuit Short to Ground Open/High Resistance Short to Voltage Signal Performanc
5 V Reference — Terminal G @ A16 Transfer Case Four Wheel Drive Actuator C15AB 11 C15AB 13 C15AB 12 —
Signal — Terminal F @ A16 Transfer Case Four Wheel Drive Actuator C05FB 11 C05FB 13 C05FB 12 C05FB 29, 38
Signal — Terminal E @ A16 Transfer Case Four Wheel Drive Actuator C11B9 11 C11B9 13 C11B9 12 C11B9 38
Low Reference — Terminal H @ A16 Transfer Case Four Wheel Drive Actuator — C15C1 13 — —

Circuit/System Description For an overview of the component/system, refer to: Transfer Case Description and Operation

Circuit Description
5 V Reference — Terminal G @ A16 Transfer Case Four Wheel Drive Actuator Regulated voltage supplied by the control module.
Circuit Description
Signal — Terminal F @ A16 Transfer Case Four Wheel Drive Actuator The control module input circuit has an internal resistance connected to 5 V.
Signal — Terminal E @ A16 Transfer Case Four Wheel Drive Actuator The control module input circuit has an internal resistance connected to ground.
Low Reference — Terminal H @ A16 Transfer Case Four Wheel Drive Actuator Grounded through the control module.
Component Description
A16 Transfer Case Four Wheel Drive Actuator The motor is bidirectional.
K69 Transfer Case Control Module The control module contains a microprocessor used to process input data to control outputs.

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 C05FB 12 Range Actuator Position Sensor = Greater than 4.7 V C05FB 11 Range Actuator Position Sensor = Less than 0.5 V C05FB 13 Range Actuator Position Sensor = 0 Hz Range Actuator Position Sensor = 2.38 to 3.49 V C05FB 29 Range Actuator Position Sensor = Greater than 5 Hz C05FB 38 Range Actuator Position Sensor = Greater than 2000 Hz C11B9 12 Range Actuator Position Sensor Direction Signal = Greater than 4.731 V C11B9 11 Range Actuator Position Sensor Direction Signal = Less than 0.53 V C11B9 13 Range Actuator Position Sensor Direction Signal = 0 Hz Range Actuator Position Sensor Direction Signal = 2.38 to 3.49 V C11B9 38 Range Actuator Position Sensor Direction Signal = Greater than 2000 Hz C15AB 12 Range Actuator Position Sensor Supply Voltage = Greater than 5.21 V C15AB 11 Range Actuator Position Sensor Supply Voltage = Less than 4.76 V C15AB 13 Condition 1 Range Actuator Position Sensor = 0 Hz Range Actuator Position Sensor = 0.944 to 2.3792 V Condition 2 Range Actuator Position Sensor Direction Signal = 0 Hz Range Actuator Position Sensor Direction Signal = 0.944 to 2.3792 V C15C1 13 Condition 1 Range Actuator Position Sensor = 0 Hz Range Actuator Position Sensor = 4.1296 to 4.729 V Condition 2 Range Actuator Position Sensor Direction Signal = 0 Hz Range Actuator Position Sensor Direction Signal = 4.1296 to 4.729 V 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: Transfer Case Range Actuator Correlation Learn 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. Perform the scan tool configuration/reset function: Transfer Case Range Actuator Correlation Learn
  3. Wait 10 s before proceeding to the next step.
  4. Ignition/Vehicle » Off
  5. Wait 30 s before proceeding to the next step.
  6. Ignition » On / Vehicle » In Service Mode
  7. Verify DTC C05FB, C11B9, C15AB, C15C1 is not set. ⇒ If the DTC is set Refer to: Circuit/System Testing ⇓ If the DTC is not set
  8. Operate the vehicle within the Conditions for Running the DTC. Verify the DTC does not set. ⇒ If the DTC sets Refer to: Circuit/System Testing ⇓ If the DTC is not set
  9. All OK. Circuit/System Testing
  1. Ignition/Vehicle & All vehicle systems » Off
  2. Disconnect the electrical connector: A16 Transfer Case Four Wheel Drive Actuator
  3. Test for less than 10 Ω between the test points: Low Reference circuit terminal H & Ground ⇒ If 10 Ω or greater 3.1. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 3.2. Test for less than 2 Ω between the test points: Low Reference circuit terminal H @ Component harness & Terminal 36 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K69 Transfer Case Control Module ⇓ If less than 10 Ω
  4. Ignition » On / Vehicle » In Service Mode
  5. Test for 4.8 to 5.2 V between the test points: 5 V Reference circuit terminal G & Low Reference circuit terminal H ⇒ If less than 4.8 V 5.1. Ignition/Vehicle » Off 5.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 5.3. Test for infinite resistance between the test points: 5 V Reference circuit terminal G @ Component harness & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇓ If infinite resistance 5.4. Test for less than 2 Ω between the test points: 5 V Reference circuit terminal G @ Component harness & Terminal 31 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K69 Transfer Case Control Module ⇒ If greater than 5.2 V 5.1. Ignition/Vehicle » Off 5.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 5.3. Ignition » On / Vehicle » In Service Mode 5.4. Test for less than 1 V between the test points: 5 V Reference circuit terminal G @ Component harness & Ground ⇒ If 1 V or greater » Repair the short to voltage on the circuit. ⇒ If less than 1 V » Replace the component: K69 Transfer Case Control Module ⇓ If between 4.8 and 5.2 V
  6. Verify DTC is not set: C05FB 12 C05FB 11 ⇒ If the DTC is set 6.1. Ignition/Vehicle » Off 6.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 6.3. Ignition » On / Vehicle » In Service Mode 6.4. Test for less than 1 V between the test points: Signal circuit terminal F @ Component harness & Ground ⇒ If 1 V or greater » Repair the short to voltage on the circuit. ⇓ If less than 1 V 6.5. Ignition/Vehicle » Off 6.6. Test for infinite resistance between the test points: Signal circuit terminal F @ Component harness & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇒ If infinite resistance » Replace the component: K69 Transfer Case Control Module ⇓ If the DTC is not set
  7. Verify DTC is not set: C11B9 12 C11B9 11 ⇒ If the DTC is set 7.1. Ignition/Vehicle » Off 7.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 7.3. Ignition » On / Vehicle » In Service Mode 7.4. Test for less than 1 V between the test points: Signal circuit terminal E @ Component harness & Ground ⇒ If 1 V or greater » Repair the short to voltage on the circuit. ⇓ If less than 1 V 7.5. Ignition/Vehicle » Off 7.6. Test for infinite resistance between the test points: Signal circuit terminal E @ Component harness & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇒ If infinite resistance » Replace the component: K69 Transfer Case Control Module ⇓ If the DTC is not set
  8. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal F & Low Reference circuit terminal H
  9. Clear DTCs
  10. Verify DTC C05FB 13 is not set. ⇒ If the DTC is set 10.1. Ignition/Vehicle » Off & Remove » Jumper wire(s) 10.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 10.3. Test for less than 2 Ω between the test points: Signal circuit terminal F @ Component harness & Terminal 19 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K69 Transfer Case Control Module ⇓ If the DTC is not set
  11. Connect a 3 A fused jumper wire between the test points: Signal circuit terminal E & Low Reference circuit terminal H
  12. Clear DTCs
  13. Verify DTC C11B9 13 is not set. ⇒ If the DTC is set 13.1. Ignition/Vehicle » Off & Remove » Jumper wire(s) 13.2. Disconnect the electrical connector: X1 @ K69 Transfer Case Control Module 13.3. Test for less than 2 Ω between the test points: Signal circuit terminal E @ Component harness & Terminal 7 @ Control module harness ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Replace the component: K69 Transfer Case Control Module ⇓ If the DTC is not set
  14. Test or replace the component: A16 Transfer Case Four Wheel Drive Actuator Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Perform the scan tool configuration/reset function: Transfer Case Range Actuator Correlation Learn Transfer Case Two/Four Wheel Drive Actuator Replacement — A16 Transfer Case Four Wheel Drive Actuator For control module replacement, programming, and setup refer to: Control Module References