Thermostat Monitor
OBD System Description - Thermostat MonitorSystem Description / Monitoring Procedure
The system accumulates the intake air quantity to simulate the engine operating condition as the warm up counter.
The thermostat is considered malfunctioning if the coolant temperature does not reach 75 degrees C at which the thermostat is at the regulating temperature (82 degrees C) within 11 degrees C. The time interval
required for monitoring is based on the accumulated intake air quantity.
1. Time interval required for monitoring: Approximately 15 minutes maximum
2. Monitoring condition: engine start ECT=-8 to 65 degrees C
DTC Description / Detecting Condition / Confirmation Procedure
P0128
Refer to DTC P0128: Coolant Thermostat (Coolant Temperature below Thermostat Regulating Temperature). P0128
Thermostat Monitor