LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1704 (Engine Controls And Fuel - 3.6L (LCS) - DTC P0638 To DTC P2229) >> DTC P0638, P2100, P2101, or P2119 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, open the hood to disable the Auto-Stop function.
  2. Ignition ON, verify the scan tool hood position parameter displays Open.
    • If the hood position does not display Open, refer to DTC P254F .
  3. Inspect the throttle body for the following conditions:
    • A throttle blade that is not in the rest position
    • A throttle valve that is binding open or closed
    • A throttle valve that opens or closes without spring pressure
    • If a condition is found, replace the throttle body.
    4. NOTE: Disconnecting the throttle body harness connector causes additional DTCs to set.
  4. Ignition OFF, disconnect the harness connector of the throttle body.
  5. Ignition ON, test for 4.0-4.2 V between the TAC motor control 1 circuit terminal B and ground.
    • If greater than the specified range, test each of the motor control circuits for a short to voltage. If the circuits tests normal, replace the ECM.
    • If less than the specified range, test the motor control 1 circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  6. Connect a test lamp between the TAC motor control 2 circuit terminal A and B+. The test lamp should NOT illuminate.
    • If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the ECM.
  7. Test for greater than 3.5 V between TAC motor control 1 circuit terminal B and TAC motor control 2 circuit terminal A.
    • If less than the specified value, test the motor control 2 circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
  8. Ignition OFF, connect the J 34730-405:  injector test lamp between the TAC motor control 1 and TAC motor control 2 circuits of the throttle body harness connector. Observe the injector test lamp while turning the ignition ON for 5 seconds and then OFF. Verify the injector test lamp illuminates brightly and then turns OFF.
    • If the injector test lamp does not illuminate, replace the ECM.
  9. If all circuits test normal, replace the throttle body.
scientia non olet · About LEMON Manuals