How to troubleshoot Kia Sorento Third Generation (2015-2020) cruise control issues?

Troubleshooting Kia Sorento Third Generation (2015-2020) Cruise Control Issues

Symptoms

1. Cruise Control Not Engaging: The cruise control system does not activate when the button is pressed.
2. Cruise Control Disengages Unexpectedly: The cruise control engages but turns off without pressing the brake or clutch pedal.
3. Cruise Control Speed Cannot Be Set: The system activates but does not allow the driver to set or adjust the speed.

Diagnostic Steps

1. Initial Inspection:

   • Verify that the vehicle is in proper operating condition (engine running smoothly, no warning lights).
   • Check the cruise control button on the steering wheel for damage or wear.

2. Check for DTCs (Diagnostic Trouble Codes):

   • Use an OBD-II scanner to check for any trouble codes related to the cruise control system. Specific codes to note include:
     • P0571: Cruise Control / Brake Switch A Circuit
     • P0572: Cruise Control / Brake Switch A Circuit Low
     • P0573: Cruise Control / Brake Switch A Circuit High

3. Inspect the Brake Light Switch:

   • The cruise control system relies on the brake light switch to function correctly.
   • Ensure that the brake lights operate normally.
   • If the brake lights are stuck on or do not illuminate, the switch may be faulty.

4. Check the Clutch Pedal Position Switch (for manual transmission):

   • Ensure that the clutch pedal position switch is functioning, as this is essential for cruise control operation in manual vehicles.

5. Examine the Cruise Control Module:

   • Check for signs of damage or corrosion on the cruise control module and its connectors.
   • Ensure all wiring and connectors are secure.

6. Inspect the Throttle Position Sensor (TPS):

   • A malfunctioning TPS can affect cruise control functionality.
   • Monitor TPS readings with a scan tool; they should match expected values during throttle application.

7. Test the Vehicle Speed Sensor (VSS):

   • Verify that the vehicle speed sensor is functioning correctly. A faulty VSS can prevent cruise control from engaging.
   • Check VSS readings via a scan tool to ensure they are within the expected range.

Tools Required

• OBD-II Scanner
• Multimeter
• Basic hand tools (screwdrivers, wrenches)
• Torque wrench
• Vehicle repair manual (for specific torque specs and part locations)

Repair Instructions

Step 1: Repair or Replace Brake Light Switch

• Removal:
  1. Disconnect the battery.
  2. Locate the brake light switch under the dashboard near the brake pedal.
  3. Remove the switch by unclipping or unscrewing it.
• Installation:
  1. Install the new brake light switch in the reverse order of removal.
  2. Reconnect the battery and test the brake lights.

Step 2: Repair or Replace Clutch Pedal Position Switch (if applicable)

• Removal:
  1. Disconnect the battery.
  2. Locate the clutch pedal position switch, typically mounted on the clutch pedal assembly.
  3. Disconnect the electrical connector and remove the switch.
• Installation:
  1. Install the new switch, ensuring it is properly aligned with the clutch pedal.
  2. Reconnect the battery and check functionality.

Step 3: Repair or Replace the Cruise Control Module

• Removal:
  1. Locate the cruise control module, usually near the engine compartment or under the dashboard.
  2. Disconnect the wiring harness and unbolt the module.
• Installation:
  1. Install the new module in reverse order.
  2. Reconnect the battery and verify system functionality.

Step 4: Replace the Throttle Position Sensor (if faulty)

• Removal:
  1. Locate the TPS on the throttle body.
  2. Disconnect the electrical connector and unbolt the sensor.
• Installation:
  1. Install the new TPS, ensuring it aligns correctly.
  2. Reconnect the electrical connector and perform a throttle reset if necessary.

Step 5: Replace Vehicle Speed Sensor (if faulty)

• Removal:
  1. Locate the VSS, typically on the transmission.
  2. Disconnect the electrical connector and unbolt the sensor.
• Installation:
  1. Install the new VSS, making sure to torque the bolts to specifications.
  2. Reconnect the electrical connector and test the cruise control system.

Final Steps

1. Test the Cruise Control: After completing repairs, take the vehicle for a test drive to ensure the cruise control system is functioning as expected.
2. Clear DTCs: If any trouble codes were present, use the OBD-II scanner to clear them and verify that they do not return after repairs.

By following these detailed steps, you should be able to troubleshoot and resolve cruise control issues on a Kia Sorento from the third generation (2015-2020).