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Circuit/System Testing

    IMPORTANT: If the knock sensor lead is damaged in any way, replace the KS.
  1. Ignition OFF, disconnect the harness connector at the KS.
  2. Ignition ON, test for 2.0-3.0 volts between the signal circuit terminal 1 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.
  3. Ignition ON, test for 2.0-3.0 volts between the low reference circuit terminal 2 and ground.
    • If less than the specified range, test the low reference 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 low reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. If all circuits test normal, test or replace the KS sensor.
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