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Circuit/System Testing

WARNING: This page is about a different car, the 2008 Pontiac G5 and 2008 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the X1 harness connector at the generator.
  2. Ignition ON, test for less than 1 volt between the signal circuit terminal 1 X1 and ground.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  3. Engine running, command the L-Terminal ON to 85% with a scan tool. Test for greater than 3 volts between the signal circuit terminal 1 X1 and ground.
    • 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.
  4. If all circuits test normal, test or replace the generator.
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