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Home >> Chevrolet >> 2020 >> Express 2500 LS, 6.0L Eng VIN G >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 24 (Engine Controls And Fuel - 2.8L (LWN) Diesel - Diagnostic Information And Procedures (1 Of 3)) >> Diagnostic Information and Procedures >> DTC P02E1, P02E4, or P02E5 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  1. Ignition/Vehicle - Off
  2. Verify a condition does not exist with the component : Blade @ Q20 Intake Air Flow Valve
      WARNING:

      Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.

    • Binding or Sticking @ Open/Close - Position
    • Closed @ Engine Off
    • Coking/Debris/Dirty/Ice/Visible Damage
    • Open/Close - Without spring pressure
    • If a condition exists 

      Replace the component : Q20 Intake Air Flow Valve

    • Go to next step : If no condition exists 
  3. NOTE:

    Disconnecting the component electrical connector causes additional DTCs to set.

  4. Disconnect the electrical connector : Q20 Intake Air Flow Valve
  5. Ignition - On / Vehicle - In Service Mode
  6. Test for 1.5 to 2.5 V between the test points : Control circuit terminal 1 & Ground
    • If less than 1.5 V 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector : X2 @ K20 Engine Control Module
    3. Test for infinite resistance between the test points : Control circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step : If infinite resistance
    4. Test for infinite resistance between the test points : Control circuit terminal 1 & Control circuit terminal 2
      • If less than infinite resistance - Repair the short between the circuits.
      • Go to next step : If infinite resistance
    5. Test for less than 2 ohms between the test points : Control circuit terminal 1 @ Component harness & The other end of the circuit @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component : K20 Engine Control Module
    • If greater than 2.5 V 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector : X2 @ K20 Engine Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points : Control circuit terminal 1 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component : K20 Engine Control Module
    • Go to next step : If between 1.5 and 2.5 V 
  7. Verify a test lamp does not turn On between the test points : Control circuit terminal 2 & B+
    • If the test lamp turns On 
    1. Ignition/Vehicle - Off Remove - Test Lamp
    2. Disconnect the electrical connector : X2 @ K20 Engine Control Module
    3. Test for infinite resistance between the test points : Control circuit terminal 1 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component : K20 Engine Control Module
    • Go to next step : If the test lamp does not turn On 
  8. Verify a test lamp does not turn On between the test points : Control circuit terminal 2 & Ground
    • If the test lamp turns On 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector : X2 @ K20 Engine Control Module
    3. Ignition - On / Vehicle - In Service Mode
    4. Test for less than 1 V between the test points : Control circuit terminal 2 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component : K20 Engine Control Module
    • Go to next step : If the test lamp does not turn On 
  9. Test for 1.5 to 2.5 V between the test points : Control circuit terminal 1 & Control circuit terminal 2
    • If not between 1.5 and 2.5 V 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector : X2 @ K20 Engine Control Module
    3. Test for less than 2 ohms between the test points : Control circuit terminal 2 @ Component harness & The other end of the circuit @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component : K20 Engine Control Module
    • Go to next step : If between 1.5 and 2.5 V 
  10. Test or replace the component : Q20 Intake Air Flow Valve