LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2006 >> Lucerne CXS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 4.6L - DTC P1400 To DTC P2444 >> DTC P2430 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the AIR solenoid valve.
  2. Ignition OFF, test for less than 1 ohm of resistance between the low reference circuit terminal and ground.
    • If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal and ground.
    • If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
    • If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Verify the scan tool AIR Pressure Sensor parameter is less than 0.5 volts.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Install a 3-amp fused jumper wire between the signal circuit terminal and the 5-volt reference circuit terminal. Verify the scan tool AIR Pressure Sensor parameter is greater than 4.9 volts.
    • If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  6. Ignition OFF, connect all wiring harness connectors.
  7. Engine running, enable the AIR system with a scan tool and observe that the AIR Pressure Sensor parameter equals approximately 8-10 kPa above BARO.
    • If not within the specified range, continue with this procedure.
  8. Remove the AIR inlet hose from the AIR pump.
  9. Engine running, enable the AIR system with a scan tool and observe that the AIR Pressure Sensor parameter increases to 8-10 kPa above BARO.
    • If within the specified range, the AIR pump inlet hoses/pipes are restricted. Remove the restriction or replace the hose/pipe.
    • If not within the specified range, continue with this procedure.
  10. Disconnect the hose from the AIR pump outlet.
  11. Disconnect the AIR outlet hose from the AIR solenoid valve inlet.
  12. Install a length of standard 1 in I.D. (25.4 mm) hose from the AIR pump outlet to the AIR solenoid valve inlet.
  13. Engine running, enable the AIR system with a scan tool and observe that the AIR Pressure Sensor parameter increases to 8-10 kPa above BARO.
    • If within the specified range, the AIR pump outlet hoses/pipes are restricted or leaking. Remove the restriction or replace the hose/pipe.
    • If less than the specified range, replace the AIR pump.
    • If more than the specified range, continue with this procedure.
  14. Remove the AIR solenoid valve.
  15. Leave the standard hose and harness connector connected.
  16. Engine running, enable the AIR system with a scan tool and observe that the AIR Pressure Sensor parameter increases to approximately 7 kPa BARO.
    • If more than the specified range, replace the AIR solenoid valve.
    • If within the specified range, the AIR solenoid valve outlet pipe or the exhaust system is restricted. Remove the restriction or replace the appropriate component.
scientia non olet · About LEMON Manuals