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Home >> Chevrolet >> 2006 >> Impala LTZ >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - 3.9L - DTC P0010 To DTC P0420 >> DTC P0335 or P0336 >> Circuit/System Testing
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Circuit/System Testing

  1. With the ignition OFF, inspect the engine wiring harnesses carrying the CKP sensor circuits for the following conditions:
    • Close routing of secondary ignition wires
    • Close routing of aftermarket electrical equipment
    • Close to solenoids, motors, and relays
    • Correct any wire harness routing or component placement conditions, if it is determined to be a possible source of electrical interference.
  2. Disconnect the CKP sensor connector.
  3. With the ignition ON and the engine OFF, measure for 4.8-5.2 volts at the connector between the 5-volt reference circuit of the CKP sensor and a good ground.
    • If the voltage is less than 4.8 volts, test for an open in the 5-volt reference circuit between the ECM and the CKP sensor connector, or a faulty ECM.
  4. With the ignition ON and the engine OFF, measure for 4.8-5.2 volts at the connector between the CKP sensor signal circuit and a good ground.
    • If the voltage is less than 4.8 volts, test for an open or a short to ground in the CKP sensor signal circuit between the ECM and the CKP sensor connector, or a faulty ECM.
    • If the voltage is more than 5.2 volts, test for a short to voltage in the CKP sensor signal circuit between the ECM and the CKP sensor connector, or a faulty ECM.
  5. With the ignition ON and the engine OFF, measure for 1-3 mA at the connector between the CKP sensor signal circuit and a good ground.
    • If the amperage is more than 3 mA, test the CKP sensor signal circuit for a short to the 5-volt reference circuit between the ECM and the CKP sensor connector, or a faulty ECM.
  6. Connect a fused jumper wire to a good ground.
  7. With the ignition ON and the engine OFF, observe the CKP Active Counter parameter on the scan tool.
  8. Touch the jumper wire to the CKP sensor signal circuit repeatedly at the connector. The CKP Active Counter parameter should increment.
    • If the CKP Active Counter parameter does not increment, replace the ECM.
  9. With the ignition ON and the engine OFF, measure for B+ at the connector between the low reference circuit of the CKP sensor and the battery positive post.
    • If the voltage measured between the low reference circuit and the battery positive post is not the same as voltage measured between a good ground and the battery positive post, test for an open/high resistance in the low reference circuit between the ECM and the CKP sensor connector, or a faulty ECM.
  10. With the ignition OFF, inspect the CKP sensor for looseness. Remove the CKP sensor from the engine, inspect the sensor and the O-ring for damage.
    • Repair or replace the CKP sensor, if necessary.
  11. Reconnect the connector to the CKP sensor.
  12. Turn ON the ignition, with the engine OFF.
  13. While observing the CKP Active Counter parameter on the scan tool, pass a steel object by the tip of the sensor repeatedly. The CKP Active Counter parameter should increment.
    • If the parameter remains at 0 or another fixed value, replace the CKP sensor.
  14. With the ignition OFF, remove the oil pan. Refer to Oil Pan Replacement and inspect the engine oil for debris and the crankshaft reluctor wheel for damage or debris stuck in the teeth.
    • If debris is found in the engine oil, inspect the engine components to determine the cause.
    • If the crankshaft reluctor wheel is damaged, replace the crankshaft.
  15. With the ignition OFF, remove the engine front cover. Refer to Engine Front Cover Replacement and inspect the timing chain, tensioner, and sprockets for wear or damage. Refer to Timing Chain and Sprockets Cleaning and Inspection .
    • If any parts are worn or damaged, replace as necessary.
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