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Circuit/System Testing

WARNING: This page is about a different car, the 2007 Chevrolet Corvette. 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. Ignition OFF, test for B+ between the generator sense circuit terminal D and ground.
    • If less than the specified range, test the generator sense circuit for a short to ground, an open/high resistance.
  3. Ignition ON, test for less than 1 volt between the generator turn on signal terminal B and ground.
    • If greater than the specified range, test the generator turn on signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Engine running, test for greater than 3.5 volts between the generator turn on signal and ground.
    • If less than the specified range, test the generator turn on signal circuit for a short to ground, an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If the circuit test normal, replace the generator.
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