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Home >> Chevrolet >> 2014 >> Traverse LS, 4D Utility >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 3.6L (LLT) - DTC P0010 To DTC P0336 >> Diagnostic Information and Procedures >> DTC P0191 >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF and all vehicle systems OFF, disconnect the multi-way harness connector X161 at the rear of the intake manifold. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 5 Ω between the low reference circuit terminal 5 and ground.
    NOTE: Testing for steps  2 through  5 is performed on the K20 Engine Control Module side of the multi-way harness connector.
    • If 5 Ω or greater 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • If less than 5 Ω 
  3. Ignition ON.
  4. Test for 4.8-5.2 V between the 5 V reference circuit terminal 11 and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the 5 V reference circuit and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1 V between the 5 V reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
    • If within the specified range 
  5. Ignition ON, verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.
    • If 0.02 V or greater 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal 12 and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
    • If less than 0.02 V 
  6. Install a 3 A fused jumper wire between the signal circuit terminal 12 and the 5 V reference circuit terminal 11.
  7. Verify the scan tool Fuel Rail Pressure Sensor Voltage parameter is greater than 4.96 V.
    • If 4.96 V or less 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the signal circuit terminal 12 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    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 K20 Engine Control Module.
    • If greater than 4.96 V 
  8. Ignition OFF, remove the intake manifold.
  9. Connect the multi-way harness connector X161.
  10. Disconnect the B47B Fuel Rail Pressure Sensor connector.
  11. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down.
    NOTE: Testing for steps  11 through  18 are performed at the fuel rail pressure sensor connector.
  12. Test for less than 5 Ω between the low reference circuit terminal 1 and ground.
    • If 5 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 5 Ω 
  13. Ignition ON.
  14. Test for 4.8-5.2 V between the 5 V reference circuit terminal 3 and ground.
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the 5 V reference circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, repair the open/high resistance in the circuit.
    • If greater than 5.2 V 

      Repair the short to voltage in the circuit.

    • If within the specified range 
  15. Ignition ON, verify the scan tool Fuel Rail Pressure Sensor voltage parameter is less than 0.02 V.
    • If 0.02 V or greater 

      Repair the short to voltage on the signal circuit.

    • If less than 0.02 V 
  16. Connect a 3 A fused jumper wire between the signal circuit terminal 2 and the 5 V reference circuit terminal 3.
  17. Verify the scan tool Fuel Rail Pressure Sensor Voltage parameter is greater than 4.96 V.
    • If 4.96 V or less 
    1. Ignition OFF, disconnect the X2 harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the signal circuit terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, repair the open/high resistance in the circuit.
    • If greater than 4.96 V 
  18. Test or replace the B47B Fuel Rail Pressure Sensor.