Outline Of Diagnosis

Detect malfunctions of the thermostat function.

Judge as NG when any one of the following conditions is established.

• When the actual engine coolant temperature does not reach the maximum temperature for executing other OBDII diagnosis and Σ(Estimated engine coolant temperature - Actual engine coolant temperature) exceeds the predetermined value (judgment 1)
• When the actual engine coolant temperature does not reach the range within -11°C (-19.8°F) from the regulated temperature and Σ(Estimated engine coolant temperature - actual engine coolant temperature) exceeded the predetermined value. (Judgment 2)