P0116

2GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0116: Engine Coolant Temperature Circuit Range / Performance Problem
P0116 - Engine Coolant Temperature Circuit Range / Performance Problem

DESCRIPTION

A thermistor is built into the Engine Coolant Temperature (ECT) sensor, of which the resistance value varies according to the ECT.

The structure of the sensor and its connection to the ECM are the same as those of the Intake Air Temperature (IAT) 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 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.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

All





Cold Start Monitor





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 engine switch on (IG) and turn the Techstream on.

3. Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.

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

5. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) Reading and Clearing Diagnostic Trouble Codes.

6. Turn the engine switch off and wait for 30 seconds.

7. Turn the engine switch on (IG) 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 engine coolant temperature sensor is malfunctioning. It is not necessary to continue this procedure.

9. Enter the following menus: Powertrain / Engine / Trouble Codes / Pending.

10. Read the pending DTC [C].

11. If a pending DTC is output, the system is malfunctioning.

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

12. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

13. Input the DTC: P0116.

14. Check the DTC judgment result.





HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.
- If the judgment result shows INCOMPLETE or N/A, perform steps [D] and [E].

15. Drive the vehicle at 25 mph (40 km/h) 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.

16. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

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

HINT
- If the judgment result shows ABNORMAL, the system has a malfunction.
- If the judgment result shows NORMAL, the system is normal.

18. If the test result is INCOMPLETE or N/A and 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 any of DTCs P0115, P0117 or P0118 are output simultaneously with DTC P0116, the engine coolant temperature sensor may have an open or a short circuit. Troubleshoot those DTCs first.
- Read freeze frame data using the 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.
- When the DTC is output, check the engine coolant temperature using the Techstream. Enter the following menus: Powertrain / Engine / Data List / Coolant Temp. If the Coolant Temp value is lower than the actual engine coolant temperature, the engine coolant temperature sensor circuit may be malfunctioning. In this case, check the wire harnesses and connectors (and those connections) between the ECM and the engine coolant temperature sensor first.

PROCEDURE

1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0116)

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

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

(e) Read the DTCs.

Result:





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

2. INSPECT THERMOSTAT

(a) Remove the thermostat Removal.

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

Standard:

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.

(c) Reinstall the thermostat Installation.

NG -- REPLACE THERMOSTAT Removal

OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal