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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the VSS.
  2. Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal A and ground.
    • If greater than the specified range, repair the ground circuit for an open/high resistance.
  3. Ignition ON, verify that a test lamp illuminates between the ignition 1 voltage circuit terminal C and ground.
    • If the test lamp does not illuminate, test the ignition 1 voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition 1 voltage circuit fuse is open, test all components connected to the ignition 1 voltage circuit and replace as necessary.
  4. Test for 9-11 volts between the signal circuit terminal B 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.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  5. If the voltage is within the specified range, test or replace the VSS.