LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2017 >> Malibu LS >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 28 (Engine Controls And Fuel - 1.8L (LKN) - DTC P0010 To P0459) >> Diagnostic Information and Procedures >> DTC P0403, P0489 or P0490: Exhaust Gas Recirculation (EGR) Control Circuit >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  1. Vehicle OFF and all vehicle systems OFF, disconnect the harness connector at the Q14 Exhaust Gas Recirculation Valve.
  2. Test for less than 10 Ω between the motor ground circuit terminal 2 and ground.
    • If 10 Ω or greater 
    1. Vehicle OFF.
    2. Test for less than 2 Ω in the motor ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Ignition ON/Vehicle in Service Mode.
  4. Verify the fuse is not open: F84UA Fuse
    • If the fuse is open 
    1. Vehicle OFF.
    2. Disconnect all components on the fused circuit.
      NOTE: A short circuit in any component supplied by the fuse may cause the fuse to open and set a DTC when the component is activated.
    3. Test for infinite resistance between the motor ignition circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, test all components supplied by the fuse and replace as necessary.
    • If the fuse is not open 
  5. Test for greater than 1 V between the test points: Ignition circuit terminal 1 & Ground
    • If less than 1 V 
    1. Vehicle OFF.
    2. Test for less than 2 Ω in the motor ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    • If greater than 1 V 
  6. Vehicle OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down.
  7. Test for less than 10 Ω between the low reference circuit terminal 5 and ground.
    • If 10 Ω or greater 
    1. Vehicle OFF, disconnect the 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 10 Ω 
  8. Ignition ON/Vehicle in Service Mode.
  9. Test for greater than 1 V between the test points: Signal circuit terminal 3 & Ground
    • If less than 1 V 
    1. Vehicle OFF.
    2. Disconnect the harness connector at the K20 Engine Control Module.
    3. Test for less than 2 Ω in the input signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Test for infinite resistance between the input signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K20 Engine Control Module
    • If greater than 1 V 
  10. Vehicle OFF, disconnect the harness connector at the K20 Engine Control Module, Ignition ON/Vehicle in Service Mode.
  11. Test for less than 1 V between the input signal circuit and ground.
    • If 1 V or greater 

      Repair the short to voltage on the circuit.

    • If less than 1 V 
  12. Vehicle OFF, connect the harness connector at the K20 Engine Control Module, Ignition ON/Vehicle in Service Mode.
  13. Test for greater than 1 V between the test points: Signal circuit terminal 4 & Ground
    • If less than 1 V 
    1. Vehicle OFF.
    2. Disconnect the harness connector at the K20 Engine Control Module.
    3. Test for less than 2 Ω in the output signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω
    4. Test for infinite resistance between the output signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K20 Engine Control Module
    • If greater than 1 V 
  14. Vehicle OFF, disconnect the harness connector at the K20 Engine Control Module, Ignition ON/Vehicle in Service Mode.
  15. Test for less than 1 V between the output signal circuit and ground.
    • If 1 V or greater,  repair the short to voltage on the circuit.
    • If less than 1 V 
  16. Test or replace the Q14 Exhaust Gas Recirculation Valve.
scientia non olet · About LEMON Manuals