P0116

1NZ-FXE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0116: Engine Coolant Temperature Circuit Range / Performance Problem

DTC P0116 - Engine Coolant Temperature Circuit Range / Performance Problem

DESCRIPTION

A thermistor is built in the engine coolant temperature sensor and changes its resistance value according to the engine coolant temperature.
The structure of the sensor and connection to the ECM are the same as those of the intake air temperature sensor.






MONITOR DESCRIPTION

Engine coolant temperature (ECT) sensor cold start monitor

When a cold engine start is performed and then the engine is warmed up, if the ECT sensor value does not change, it is determined that a malfunction has occurred. If this is detected in 2 consecutive driving cycles, the MIL is illuminated and a DTC is set.

ECT sensor soak monitor

After a warmed up engine is started, if the ECT sensor value does not change when the engine is stopped and then the next cold engine start is performed, it is determined that a malfunction has occurred. If this is detected in 2 consecutive driving cycles, the MIL is illuminated and a DTC is set.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

ECT sensor cold start monitor:





ECT sensor soak monitor:





TYPICAL MALFUNCTION THRESHOLDS

Engine Coolant Temperature Sensor Cold Start Monitor:





Engine Coolant Temperature Sensor Soak Monitor:





COMPONENT OPERATING RANGE





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. READ OUTPUT DTC
(a) Connect Techstream to the DLC3.
(b) Turn the power switch ON (IG) and turn the tester on.
(c) Select the following menu items: Powertrain / Engine and ECT / Trouble Code.
(d) Read the DTCs.
Result:






B -- GO TO DTC CHART
A -- Continue to next step.

2. INSPECT THERMOSTAT
(a) Remove the thermostat Removal.
(b) Measure the valve opening temperature of the thermostat.
Standard temperature:
80°C to 84°C (176°F to 183°F)
HINT: In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.
(c) Reinstall the thermostat Installation.
NG -- REPLACE THERMOSTAT
OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR