OBD System Description - Thermostat Monitor

OBD System Description - Thermostat Monitor

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

DTC Description/Detecting/Confirmation Procedure

P0128
Refer to DTC P0116/P0125/P0128. P0116

Thermostat Monitor

Operation






Enabled conditions






Typical malfunction thresholds