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Home >> Chevrolet >> 2006 >> Optra5 LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 2.0L (L34 GMDAT) - DTC P0404 To DTC P2110 >> DTC P0498 or P0499 >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector of the EVAP vent solenoid valve.
    2. IMPORTANT: The test lamp is used to load the circuit and may not illuminate.
  2. Connect a test lamp between the ignition 1 voltage circuit of the EVAP vent solenoid valve and the negative terminal of the battery.
  3. Ignition ON, test for less than 0.1 volt between the ignition 1 voltage circuit of the EVAP vent solenoid valve and the positive terminal of the battery.
    • If greater than 0.1 volt, repair the ignition 1 voltage circuit of the EVAP vent solenoid valve for a short to ground or an open/high resistance.
  4. With the ignition OFF, connect a test lamp between the control circuit and the ignition 1 voltage circuit of the EVAP vent solenoid valve.
  5. With the ignition ON, use a scan tool to command the EVAP vent solenoid valve ON. The test lamp should pulse ON and OFF for about 3-5 seconds.
    • If the test lamp remains ON all the time, test for a short to ground on the control circuit. If circuit/connections test normal, replace the ECM.
    • If the test lamp remains OFF all the time, test for a short to voltage or an open/high resistance on the control circuit. If circuit/connections test normal, replace the ECM.
  6. If all circuits/connections test normal, test or replace the EVAP vent solenoid valve.
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