Continental 2000-2002

Testing

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  1. Disconnect the engine wiring harness from the ECT sensor.
  2.  
  3. Connect an ohmmeter between the ECT sensor terminals.
  4.  
  5. With the engine cold and the ignition switch in the OFF position, measure and note the ECT sensor resistance.
  6.  
  7. Connect the engine wiring harness to the sensor.
  8.  
  9. Start the engine and allow the engine to reach normal operating temperature.
  10.  
  11. Once the engine has reached normal operating temperature, turn the engine OFF.
  12.  
  13. Once again, disconnect the engine wiring harness from the ECT sensor.
  14.  
  15. Measure and note the ECT sensor resistance with the engine hot.
  16.  
  17. Compare the cold and hot ECT sensor resistance measurements with the accompanying chart.
  18.  
  19. If readings do not approximate those in the chart, the sensor may be faulty.

    Click image to see an enlarged view

    Fig. Measure the resistance of the ECT sensor across the two sensor terminals using a suitable DVOM. Compare the readings to the temp/resistance chart



    Click image to see an enlarged view

    Fig. Another method of testing the ECT is to submerge it in cold or hot water and check resistance



    Click image to see an enlarged view

    Fig. ECT resistance-to-temperature specifications

  20.  


CAUTION
Never open, service, or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. In addition, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

The sending unit is located in a water jacket or coolant passage near the thermostat.

  1. Check the appropriate fuse before attempting any other diagnostics.
  2.  
  3. Make sure the cooling system is full and free of any trapped air.
  4.  
  5. Tape a mechanic's thermometer to the radiator return hose (upper hose) securely.
  6.  
  7. Disconnect the sending unit electrical harness.
  8.  
  9. Using an ohmmeter, check the resistance between the sending unit terminals.
  10.  
  11. Resistance should be high (58K ohms) with engine coolant cold 50°F (10°C) and low (2.8K ohms) with engine coolant hot 194°F (90°C).
  12.  


NOTE
It is best to check resistance with the engine cool, then start the engine, and watch the resistance change as the engine warms.

  1. If resistance does not drop as engine temperature rises, the sending unit is faulty.
  2.  



Click image to see an enlarged view

Fig. Another method of testing the ECT is to submerge it in cold or hot water and check resistance



Click image to see an enlarged view

Fig. ECT resistance-to-temperature specifications



Click image to see an enlarged view

Fig. Test the ECT resistance across the two sensor terminals

  1. Disconnect the engine wiring harness from the ECT sensor.
  2.  
  3. Connect an ohmmeter between the ECT sensor terminals.
  4.  
  5. With the engine cold and the ignition switch in the OFF position, measure and note the ECT sensor resistance.
  6.  
  7. Connect the engine wiring harness to the sensor.
  8.  
  9. Start the engine and allow the engine to reach normal operating temperature.
  10.  
  11. Once the engine has reached normal operating temperature, turn the engine OFF .
  12.  
  13. Again, disconnect the engine wiring harness from the ECT sensor.
  14.  
  15. Measure and note the ECT sensor resistance with the engine hot.
  16.  
  17. Compare the cold and hot ECT sensor resistance measurements with the accompanying chart.
  18.  
  19. If readings do not approximate those in the chart, the sensor may be faulty.
  20.  

 
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