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Circuit/System Testing

WARNING: This page is about a different car, the 2010 Pontiac G5 and 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify that a test lamp illuminates between the B+ circuit ring terminal 1 X2 and ground.
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  2. Ignition OFF, disconnect the X1 harness connector at the generator.
  3. Ignition ON, verify the scan tool ECM GEN-F Terminal Signal parameter is less than 5%.
    • If greater than the specified range, test the appropriate signal circuit terminal listed below for a short to voltage. If the circuit tests normal, replace the ECM.
      • Terminal 2 X1 (L61/LE5)
      • Terminal C X1 (LNF)
  4. Install a 3A fused jumper wire between the appropriate signal circuit terminal listed below and B+. Verify the scan tool ECM GEN-F Terminal Signal parameter is greater than 95%.
    • Terminal 2 X1 (L61/LE5)
    • Terminal C X1 (LNF)
    • If less than the specified range, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  5. If all circuits test normal, test or replace the generator.