P0116

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

DESCRIPTION

Refer to DTC P0115 P0115.





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 stored.

ECT sensor soak monitor

If the ECT sensor value does not change after the warmed up 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 stored.

ECT sensor high side stuck monitor (only for Mexico models)

The ECM monitors the sensor voltage and uses this value to calculate the ECT. If the sensor voltage output deviates from the normal operating range, the ECM interprets this deviation as a malfunction in the ECT sensor and sets the DTC.

Examples:

- Upon starting the engine, the ECT is between 35°C and 60°C (95°F and 140°F). If, after driving for 250 seconds, the ECT remains within 3°C (37.4°F) of the starting temperature, the DTC is set (2 trip detection logic).

- Upon starting the engine, the ECT is over 60°C (140°F). If, after driving for 250 seconds, the ECM remains within 1°C (33.8°F) of the starting temperature, the DTC is set (6 trip detection logic).

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





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the ignition switch to ON and turn the Techstream on.

3. Enter the following menu items: Powertrain / Engine and ECT / Data List / Coolant Temp.

4. Check that the coolant temperature is 60°C (140°F) or less.

5. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).

6. Turn the ignition switch off and wait for at least 30 seconds.

7. Turn the ignition switch to ON and turn the Techstream on [A].

8. Start the engine and idle it for 5 minutes or more [B].

HINT
If the engine coolant temperature does not change by 5°C (9°F) or higher, the ECT sensor is malfunctioning. It is not necessary to continue this procedure.

9. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [C].

10. Read the pending DTCs.

HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.

11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

12. Input the DTC: P0116.

13. Check the DTC judgment result.





HINT
If the judgment result shows INCOMPLETE or N/A, perform steps [D] and [E].

14. Drive the vehicle at 40 km/h (25 mph) or more for a total of 5 minutes or more [D].

CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT
In the event of the drive pattern being interrupted (possibly due to factors such as traffic conditions), the drive pattern can be resumed.

15. Check the DTC judgment result again [E].

HINT
If the judgment result shows INCOMPLETE or N/A, perform steps [D] and [E] again.

16. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.

INSPECTION PROCEDURE

HINT
* If DTC P0115, P0117, P0118 or P0125 is stored simultaneously with DTC P0116, the ECT sensor may have an open or short circuit. Troubleshoot those DTCs first.
* Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. 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 the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

(e) Read the DTCs.

Result





HINT
If any DTCs other than P0116 are output, perform troubleshooting for those DTCs first.

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

2. INSPECT THERMOSTAT

(a) Remove the thermostat Removal.

(b) Measure the valve opening temperature of the thermostat.

Standard opening temperature:

80 to 84°C (176 to 183°F)

HINT
In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.

NG -- REPLACE THERMOSTAT Removal

OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal