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OBD System Description - Thermostat Monitor (EVAP Leak Check Model)

OBD System Description - Thermostat Monitor (EVAP Leak Check Model)

System Description / Monitoring Procedure
The engine coolant temperature is estimated to model accumulated combustion heat value since engine start (based on mass intake air flow) and radiation heat value (radiation from engine, radiation when fuel shut-off, etc.). When estimated temperature reaches the specified temperature and the measured temperature is lower than criteria, the malfunction is detected.

DTC Description / Detecting / Confirmation Procedure

P0128
Refer to DTC P0116 / P0125 / P0128. P0116

Thermostat Monitor