P0116
2AZ-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0116: Engine Coolant Temperature Circuit Range / Performance Problem
DTC P0116 - Engine Coolant Temperature Circuit Range / Performance Problem
DESCRIPTION
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
ECT Sensor cold start monitor:
ECT Sensor soak monitor:
COMPONENT OPERATING RANGE
INSPECTION PROCEDURE
HINT:
- If any of DTCs P0115, P0117, P0118 or P0125 are set simultaneously with DTC P0116, the ECT sensor may have an open or a short circuit. Troubleshoot those DTCs first.
- Read freeze frame data using Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
PROCEDURE
1. CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0116)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Select the following menu items: Powertrain / Engine and ECT / Trouble Codes.
(e) 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 value:
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