LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2015 >> Regal GS, AWD >> Repair and Diagnosis >> Engine Performance >> Testing & Diagnosis >> Engine Controls And Fuel - 2.0L (LTG) - DTC P0010 To DTC P0333 >> Diagnostic Information and Procedures >> DTC P0090-P0092, P00C8, P00C9, or P00CA: Fuel Pressure Regulator >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the G18 High Pressure Fuel Pump.
  2. Ignition ON, verify that a test lamp does not illuminate between the high control circuit terminal 1 and ground and the low control circuit terminal 2 and ground.
    • If the test lamp illuminates 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1V between the appropriate control circuit and ground.
      • If 1V or greater, repair the short to voltage on the circuit.
      • If less than 1V, replace the K20 Engine Control Module.
    • If the test lamp does not illuminate 
  3. Verify that a test lamp does not illuminate between the high control circuit terminal 1 and B+ and the low control circuit terminal 2 and B+.
    • If the test lamp illuminates 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the appropriate control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2Ω in the control circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K20 Engine Control Module.
    • If the test lamp does not illuminate 
  4. Connect a 3A fused jumper wire between the high control circuit terminal 1 and ground.
  5. Verify the Fuel Pressure Regulator High Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator High Control Circuit Low Voltage Test Status transitions from OK to Malfunction.
    • The parameters do not change 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for less than 2Ω in the high control circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K20 Engine Control Module.
    • The parameters change 
  6. Connect a 3A fused jumper wire between the low control circuit terminal 2 and B+.
  7. Verify the Fuel Pressure Regulator Control Circuit Open Test Status transitions from Malfunction to OK and the Fuel Pressure Regulator Control Circuit High Voltage Test Status transitions from OK to Malfunction.
    • The parameters do not change 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for less than 2Ω in the low control circuit end to end.
      • If 2Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2Ω, replace the K20 Engine Control Module.
    • The parameters change 
  8. Test or replace the G18 High Pressure Fuel Pump.
scientia non olet · About LEMON Manuals