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Circuit/System Testing

    IMPORTANT: If the CKP sensor lead is damaged in any way, replace the CKP sensor.
  1. Ignition OFF, disconnect the harness connector of the crankshaft position (CKP) sensor.
  2. Ignition ON, verify that 1.5-2.0 volts is available on the signal circuit and the low reference circuit of the CKP sensor.
    • If less than 1.5 volts, test the applicable circuit for a short to ground or an open/high resistance. If the circuits/connections test normal, replace the ECM.
    • If more than 2.0 volts, test the applicable circuit for a short to voltage. If the circuits/connections test normal, replace the ECM.
  3. If all circuits/connections test normal, test or replace the CKP sensor.