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Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check - engine controls, go to next step.
  2. Inspect the Evaporative Emission (EVAP) system for a damaged EVAP vent solenoid, a pinched EVAP vent hose, or damaged EVAP canister. Did you find and correct the condition? If yes, go to step  17. If no, go to next step.
  3. Command the EVAP vent solenoid on and off with a scan tool. Do you hear or feel the EVAP vent solenoid click when commanded on and off? If yes, go to next step. If no, go to step  8.
  4. Turn ignition off. Disconnect the EVAP purge line from the EVAP purge solenoid. Turn ignition on, with engine off. Is the Fuel Tank Pressure Sensor parameter 1.30-1.70 volts? If yes, go to next step. If no, go to step  10.
    5. NOTE: Do not exceed the specified value in this step. Exceeding the specified value may produce incorrect test results.
  5. Turn ignition off. Connect the EVAP purge pipe. Connect the Evaporative Emissions System Tester (J-41413-200) power supply clips to a known-good 12-volt source. Install the Fuel Fill Cap Adapter (J-41415-40) to the fuel fill pipe. Connect the fuel fill cap to the J-41415-40. Connect the J-41413-200 nitrogen/smoke supply hose to the J-41415-40. Turn ignition on, with engine off. Command the EVAP vent solenoid CLOSED with a scan tool. Turn the nitrogen/smoke valve on the J-41413-200 control panel to NITROGEN. Use the remote switch to pressurize the EVAP system to 5 in. H2O on the Pressure/Vacuum Gauge (J-41750). Observe the Fuel Tank Pressure Sensor parameter with a scan tool. Command the EVAP vent solenoid open with a scan tool. Is the Fuel Tank Pressure Sensor parameter 1.30-1.70 volts? If yes, go to DIAGNOSTIC AIDS . If no, go to next step.
  6. Disconnect the EVAP vent hose from the EVAP vent solenoid. Is the Fuel Tank Pressure Sensor parameter 1.30-1.70 volts? If yes, go to step  13. If no, go to next step.
  7. Disconnect the EVAP vent hose from the EVAP canister. Is the Fuel Tank Pressure Sensor parameter less than 1.30-1.70 volts? If yes, go to step  12. If no, go to step  14.
  8. Disconnect the EVAP vent solenoid. Probe the control circuit of the EVAP vent solenoid with a test light that is connected to battery voltage. Does the test light illuminate? If yes, go to next step. If no, go to step  13.
  9. Test EVAP vent solenoid control circuit for a short to ground. Did you find and correct the condition? If yes, go to step  17. If no, go to step  11.
  10. Test for an intermittent and for a poor connection at the FTP sensor. Did you find and correct the condition? If yes, go to step  17. If no, go to step  15.
  11. Test for an intermittent and for a poor connection at the control module. Did you find and correct the condition? If yes, go to step  17. If no, go to step  16.
  12. Repair the pinched or restricted EVAP vent hose. After repairs, go to step  17.
  13. Replace EVAP vent solenoid. After replacing solenoid, go to step  17.
  14. Replace EVAP canister. After replacing canister, go to step  17.
  15. Turn ignition off. Replace ECM. Perform ECM relearn procedure. See ELECTRONIC CONTROL MODULE REPROGRAMMING  under PROGRAMMING. After replacing ECM, go to next step.
  16. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Operate vehicle within the conditions for running the DTC. See CONDITIONS FOR RUNNING DTC . You may also operate vehicle within the conditions observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition? If yes, go to step  2. If no, go to next step.
  17. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
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