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Circuit/System Testing

WARNING: This page is about a different car, the 2011 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF, disconnect the harness connector at the generator.
  2. Engine Running, command the Gernerator L-Teriminal Command OFF with a scan tool. Test for less than 1 V between the generator turn on signal circuit terminal 1 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 Generator L-Terminal Command ON with a scan tool. Test for greater than 3.5 V between the signal circuit terminal 1 and ground.
    • If less than the specified range, test the signal circuit for a short to ground, an open or a high resistance. If the circuit tests normal, replace the ECM.
  4. If the circuit tests normal, test or replace the generator.
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