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Home >> Chevrolet >> 2009 >> Impala Police >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 3.9L - DTC P0341 To DTC P2544 >> DTC P1682 >> Circuit/System Testing >> Testing the Ignition 1 Signal Circuit

Testing the Ignition 1 Signal Circuit

    IMPORTANT: A resistance of 5 ohms or greater in the circuit will cause the DTC to set.
  1. Ignition ON, verify that B+ is available to both test points of the fuse from the ignition main relay to the ECM.
    • If B+ is only available on one test point of the fuse, test the ignition 1 voltage circuit from the fuse to the ECM X1-19 for a short to ground. If the circuit tests normal, replace the ECM.
    • If B+ is not available on either test point of the fuse, replace the underhood fuse block.
  2. Ignition OFF, disconnect the ECM X1 connector.
  3. Ignition ON, verify that B+ is available at X1-19.
    • If B+ is not available, test the ignition 1 voltage circuit for an open/high resistance condition. If the circuit tests normal, replace the ECM.
  4. If all circuits test normal, replace the ECM.
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