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6. ECT Sensor Operation

NOTE: For this test to be valid, the thermostat must be operating correctly.
NOTE: This test works best if performed on a cold engine (cold soak).

Turn the ignition off until the engine is cold.

Turn the ignition on.

With the DRB III(R), read the Engine Coolant Temperature Sensor value. If the engine was allowed to sit overnight (cold soak), the temperature value should be a sensible value that is somewhere close to the ambient temperature.

NOTE: If engine coolant temperature is above 82°C (180°F), allow the engine to cool until 65°C (150°F) is reached.

Start the Engine

During engine warm-up, monitor the Engine Coolant Temperature value. The temperature value change should be a smooth transition from start up to normal operating temperature 82°C (180°F). The value should reach at least 82°C (180°F).

Did the Engine Coolant Temperature value increase with a smooth transition and did it reach at least 82°C (180°F)? 

  1. Yes  >> Go To 7
  2. No  >> Replace the Engine Coolant Temperature Sensor. See COOLING SYSTEM (MECHANICAL) article.

    See POWERTRAIN VERIFICATION TEST - VER 2  .