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Home >> Cadillac >> 2009 >> STS Base, 3.6 V, AWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 3.6L - DTC P0008 To DTC P0193 >> DTC P0116 >> Circuit/System Testing

Circuit/System Testing

  1. Ignition OFF, disconnect the ECT sensor.
  2. Ignition ON, verify that the scan tool ECT sensor parameter is at -40°C (-40°F).
    • If greater than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM.
  3. Ignition OFF, remove the fuse that supplies B+ to circuit terminal X2-56 of the ECM.
    4. CAUTION: Do NOT use a test lamp to test the continuity of the circuit. Damage to the control module may occur due to excessive current draw.
    NOTE: The control module or the sensor may be damaged if the circuit is shorted to battery positive voltage.
  4. Test for less than 5 ohms between the low reference circuit terminal 2 and ground.
    • If greater than the specified range, test the low reference circuit for an open/high resistance, or for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Install the fuse that supplies B+ to circuit terminal X2-56 of the ECM.
    6. NOTE: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the sensor may be damaged.
  6. Ignition ON, install a 3A fused jumper wire between the signal circuit terminal 1 and the low reference circuit terminal 2. Verify the ECT sensor parameter is greater than 142°C (288°F).
    • If less than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
  7. If all circuits test normal, test or replace the ECT sensor.
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