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Tahoe / Yukon Service Manual

DTC C1159

Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC Descriptors DTC C1159 49 Steering Column Position Module Internal Malfunction DTC C1159 54 Steering Column Position Module Calibration Not Learned Diagnostic Fault Information

Circuit Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan ce
4640 B+ — 1 — —
2096 Signal C1159 49, 4 2 C1159 49, 4 —
2097 Signal C1159 49, 4 2 C1159 49, 4 —
2094 Signal C1159 49, 5 3 C1159 49, 5 —
2095 Signal C1159 49, 5 3 C1159 49, 5 —
2111 Control — 2 — —
2112 Control — 2 — —
2110 Control — 3 — —
2098 Control — 3 — —
2154 Signal C1159 49, 4 C1159 49, 4 C1159 49, 4 4
2153 Signal C1159 49, 5 C1159 49, 5 C1159 49, 5 5
2157 Low Reference — C1159 49, 4 — —
Circuit Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan
2152 Low Reference — C1159 49, 5 — —
2020 Ground — 1 — —
1850 Ground — 1 — —
1. Column Tilt Wheel and Telescope Inoperative 2. Column Tilt Inoperative 3. Column Telescope Inoperative 4. Column Tilt Wheel Actuator Inoperative\Erratic 5. Column Telescope Actuator Inoperative\Erratic

Circuit/System Description The steering column has a tilt/telescoping control system that consists of a K99 Steering Column Tilt Wheel and Telescope Control Module capable of serial data communication, a steering column power assembly with positioning actuators and sensors, and a S71 Steering Column Tilt Wheel and Telescope Switch. The K99 Steering Column Tilt Wheel and Telescope Control Module will wake up either by the serial data or by the S71 Steering Column Tilt Wheel and Telescope Switch. Two position sensors are hall effect sensors and are used by the K99 Steering Column Tilt Wheel and Telescope Control Module. The K99 Steering Column Tilt Wheel and Telescope Control Module provides a 12 V reference voltage and a ground to both the tilt and telescoping position sensors. The sensor feedback circuit voltage varies from 0–12 V. Each sensor is part of the actuator assembly. The K99 Steering Column Tilt Wheel and Telescope Control Module monitors the feedback voltage to determine the column position. All DTCs and data from K99 Steering Column Tilt Wheel and Telescope Control Module is communicated through the serial data and stored in the K40D Driver Seat Adjuster Memory Module. Conditions for Running the DTC Ignition ON. Conditions for Setting the DTC C1159 49 The K99 Steering Column Tilt Wheel and Telescope Control Module has detected an internal electronic failure or external circuit malfunction. C1159 54 The K99 Steering Column Tilt Wheel and Telescope Control Module soft stops have not been learned. Action Taken When the DTC Sets The K99 Steering Column Tilt Wheel and Telescope Control Module requests the DTC to be stored in the K40D Driver Seat Adjuster Memory Module. Conditions for Clearing the DTC C1159 49 The external fault has been removed or K99 Steering Column Tilt Wheel and Telescope Control Module has been replaced. C1159 54 The Steering Column Tilt Wheel and Telescope Control Module Learn procedure has been completed. Diagnostic Aids All DTCs and data from the K99 Steering Column Tilt Wheel and Telescope Control Module is communicated through the serial data and stored in the K40D Driver Seat Adjuster Memory Module. The K40D Driver Seat Adjuster Memory Module only reports the DTCs communicated from the K99 Steering Column Tilt Wheel and Telescope Control Module. DTCs stored in the K40D Driver Seat Adjuster Memory Module for the K99 Steering Column Tilt Wheel and Telescope Control Module DOES NOT affect the operation of the seat or the seat memory. DO NOT replace the K40D Driver Seat Adjuster Memory Module when DTC C1159 is stored because the K99 Steering Column Tilt Wheel and Telescope Control Module has detected a fault within it’s system. Reference Information Schematic Reference Tilt/Telescoping Steering Column Schematics Connector End View Reference Master Electrical Component List Description and Operation Steering Wheel and Column Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Circuit/System Verification

  1. Ignition ON.
  2. Verify that DTC C1159 54 is not set. ⇒ DTC C1159 54 is set 2.1. Perform the Steering Column Tilt Wheel and Telescope Control Module Learn. Refer to Steering Column Tilt Wheel and Telescope Control Module Learn 2.2. Verify that DTC C1159 54 does not reset.
  1. Verify the scan tool Steering Column Direction Switch parameter changes between Inactive, Forward, Rearward, Up, and Down when exercising the S71 Steering Column Tilt Wheel and Telescope Switch. ⇒ If the parameter does not change Refer to Circuit/System Testing – Switch Malfunction. ⇓ If the parameter changes
  2. Verify the operation of the M68 Steering Column Tilt Wheel Actuator while commanding the Steering Column Tilt Up and Steering Column Tilt Down Command with a scan tool. ⇒ If the Steering Column Tilt Up or Steering Column Tilt Down Command does not work Refer to Circuit/System Testing – Tilt Wheel Actuator Malfunction ⇓ If the Steering Column Tilt Up and Steering Column Tilt Down Command works
  3. Verify the M65 Steering Column Telescope Actuator while commanding the Steering Column Telescope Forward and Steering Column Telescope Rearward with a scan tool. ⇒ If the Steering Column Telescope Forward and Steering Column Telescope Rearward does not work Refer to Circuit/System Testing – Telescope Actuator Malfunction ⇓ If the Steering Column Telescope Forward and Steering Column Telescope Rearward works
  4. Verify that DTC C1159 49 is not set. ⇒ If DTC C1159 49 is set
  1. All OK. Circuit/System Testing Switch Malfunction
  2. Ignition OFF, disconnect the connector at the S71 Steering Column Tilt Wheel and Telescope Switch. It may take up to 2 min for all vehicle systems to power down.
  3. Test for less than 10 Ω between the low reference circuit terminal G and ground. ⇒ If 10 Ω or greater 2.1. Ignition OFF. 2.2. Test for less than 2 Ω in the ground circuit end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the K99 Steering Column Tilt Wheel and Telescope Control Module. ⇓ If less than 10 Ω
  4. Ignition ON.
  5. Test for B+ between the signal circuit terminals listed below and ground: Terminal A Terminal B Terminal C Terminal F ⇒ If less than B+ 4.1. Ignition OFF, disconnect the X1 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module. 4.2. Test for infinite resistance between the signal circuit and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 4.3. Test for less than 2 Ω in the signal circuit end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the K99 Steering Column Tilt Wheel and Telescope Control Module. ⇓ If B+
  6. Ignition OFF, disconnect the X1 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module. It may take up to 2 min for all vehicle systems to power down.
  7. Ignition ON.
  8. Test for less than 1 V between the signal circuit terminals listed below and ground: Terminal A Terminal B Terminal C Terminal F ⇒ If greater than 1 V Repair the short to voltage on the circuit ⇓ If less than 1 V
  9. Test or replace the S71 Steering Column Tilt Wheel and Telescope Switch. Tilt Wheel Actuator Malfunction
  10. Ignition OFF, disconnect the X2 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module, ignition ON.
  11. Test for less than 1 V between each circuit terminal listed below and ground at the K99 Steering Column Tilt Wheel and Telescope Control Module harness connector. Steering Column Tilt Wheel Actuator Down Control - terminal 9 Steering Column Tilt Wheel Actuator Up Control - terminal 10 Steering Column Tilt Wheel Actuator Signal - terminal 3 ⇒ If 1 V or greater Repair the short to voltage on the circuit. ⇓ If less than 1 V
  12. Ignition OFF.
  13. Test for infinite resistance between each circuit terminal listed below and ground at the K99 Steering Column Tilt Wheel and Telescope Control Module harness connector. Steering Column Tilt Wheel Actuator Down Control - terminal 9 Steering Column Tilt Wheel Actuator Up Control - terminal 10 Steering Column Tilt Wheel Actuator Signal - terminal 3 ⇒ If less than infinite resistance Repair the short to ground on the circuit. ⇓ If Infinite resistance
  14. Replace the M68 Steering Column Tilt Wheel Actuator. Telescope Actuator Malfunction
  15. Ignition OFF, disconnect the X2 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module, ignition ON.
  16. Test for less than 1 V between each circuit terminal listed below and ground at the K99 Steering Column Tilt Wheel and Telescope Control Module harness connector. Steering Column Telescope Actuator Forward - terminal 7 Steering Column Telescope Actuator Rearward - terminal 8 Steering Column Telescope Actuator Signal - terminal 1 ⇒ If 1 V or greater Repair the short to voltage on the circuit. ⇓ If less than 1 V
  17. Ignition OFF.
  18. Test for infinite resistance between each circuit terminal listed below and ground at the K99 Steering Column Tilt Wheel and Telescope Control Module harness connector. Steering Column Telescope Actuator Forward - terminal 7 Steering Column Telescope Actuator Rearward - terminal 8 Steering Column Telescope Actuator Signal - terminal 1 ⇒ If less than infinite resistance Repair the short to ground on the circuit. ⇓ If Infinite resistance
  19. Replace the M65 Steering Column Telescope Actuator. Component Testing Steering Column Tilt Wheel and Telescope Switch Test
  20. Ignition OFF, disconnect the connector at the S71 Steering Column Tilt Wheel and Telescope Switch.
  21. Test for infinite resistance between the ground circuit terminal G and each signal circuit terminal with the S71 Steering Column Tilt Wheel and Telescope Switch in the released position. ⇒ If less than infinite resistance Replace the S71 Steering Column Tilt Wheel and Telescope Switch. ⇓ If infinite resistance
  22. Test for less than 2 Ω between the ground circuit terminal G and each signal circuit terminal with the S71 Steering Column Tilt Wheel and Telescope Switch in the pressed position. ⇒ If 2 Ω or greater Replace the S71 Steering Column Tilt Wheel and Telescope Switch. ⇓ If less than 2 Ω
  23. All OK. Steering Column Telescope Actuator Test
  24. Ignition OFF, disconnect the X2 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module.
  25. Test for 1–2.5 Ω between terminal 7 and terminal 8. ⇒ If not within the specified range Replace the M65 Steering Column Telescope Actuator. ⇓ If within the specified range
  26. All OK. Steering Column Tilt Wheel Actuator Test
  27. Ignition OFF, disconnect the X2 connector at the K99 Steering Column Tilt Wheel and Telescope Control Module.
  28. Test for 1–2.5 Ω between terminal 9 and terminal 10. ⇒ If not within the specified range Replace the M68 Steering Column Tilt Wheel Actuator. ⇓ If within the specified range
  29. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Control Module References for control module replacement, programming, and setup