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P0116





2AZ-FE ENGINE CONTROL: 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 sensor (ECT) sensor cold monitor

The monitor runs when the engine is started cold. If the change in engine coolant temperature sensor output until the engine warmed up completely is less than the threshold, it is determined that a malfunction has occurred in the engine coolant temperature sensor. When this is detected in 2 consecutive driving cycles, the MIL illuminated and the DTC is set.

ECT sensor soak monitor

The ECM compares the engine coolant temperature when the warmed engine is stopped and when the engine is started on the next trip when more than 5 hours has elapsed since the engine was stopped. If the change in engine coolant temperature sensor output is less than the threshold, it is determined that a malfunction has occurred in the engine coolant temperature sensor. When this is detected in 2 consecutive driving cycles, the MIL is illuminated and the DTC is set.

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

Engine Coolant Temperature Sensor Cold Start Monitor

Engine Coolant Temperature Sensor Cold Start Monitor:





Engine Coolant Temperature Sensor Soak Monitor

Engine Coolant Temperature Sensor Soak Monitor:





TYPICAL MALFUNCTION THRESHOLDS

Engine Coolant Temperature Sensor Cold Start Monitor

Engine Coolant Temperature Sensor Cold Start Monitor:





Engine Coolant Temperature Sensor Soak Monitor

Engine Coolant Temperature 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 the DTCs (even if no DTCs are stored, perform the clear DTC procedure) DTC Check / Clear.

6. Turn the ignition switch off.

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 engine coolant temperature sensor is malfunctioning. It is not necessary to continue this procedure.

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

10. Input the DTC: P0116.

11. Check the DTC judgment result [C].





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

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

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

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

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

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

14. If the test result is UNKNOWN, enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.

15. Read Pending DTCs.

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

16. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.

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, P0118 or P0125 are set 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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

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 DTCs.

Result:





B -- GO TO DTC CHART Engine Control System - 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 Value:

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 Components

OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Components