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Home >> Chevrolet >> 2015 >> Spark LS, Automatic CVT Trans >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 1.2L - Diagnostic Information And Procedures >> Diagnostic Information and Procedures >> DTC P0628: Fuel Pump Relay Control Circuit >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF and all vehicle systems OFF, disconnect the KR23A Fuel Pump Relay. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 10 Ω between the ground circuit terminal 85 and ground.
    • If 10 Ω or greater 
    1. Ignition OFF.
    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, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  3. Verify that a test lamp does not illuminate between the control circuit terminal 86 and ground.
    • If the test lamp illuminates 
    1. Ignition OFF, disconnect the X1 harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1 V between the control 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 the test lamp does not illuminate 
  4. Remove the test lamp.
  5. Verify the scan tool Fuel Pump Relay Control Circuit Low Voltage Test Status parameter is OK when commanding the Fuel Pump Relay On with a scan tool.
    • If OK is not displayed 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the control 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 OK is displayed 
  6. Install a 3 A fused jumper wire between the control circuit terminal 86 and the ground circuit terminal 85.
  7. Verify the scan tool Fuel Pump Relay Control Circuit Low Voltage Test Status parameter is Malfunction when commanding the Fuel Pump Relay On with a scan tool.
    • If Malfunction is not displayed 
    1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for less than 2 Ω in the control 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 Malfunction is displayed 
  8. Replace the KR23A Fuel Pump Relay.
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