Thermostat Monitor
OBD System Description - Thermostat Monitor
System Description / Monitoring Procedure
The engine coolant temperature is estimated to model accumulated combustion heat value since engine start (based on intake mass 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 ECM will set DTC.
DTC Description / Detecting Condition / Confirmation Procedure
P0128
Refer to DTC P0116 / P011B / P0128 P0116
Thermostat Monitor
Operation
Enable Conditions
Typical malfunction thresholds