P0116

3UZ-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

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

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 set.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





Cold start monitor:





Soak monitor:





TYPICAL MALFUNCTION THRESHOLDS

Cold start monitor:





Soak monitor:





COMPONENT OPERATING RANGE





CONFIRMATION DRIVING PATTERN





- Connect the Techstream to the DLC3.

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

- Enter the following menu items: Powertrain / Engine / Data List / Coolant Temp.

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

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

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

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

- 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.

- Enter the following menus: Powertrain / Engine / Trouble Codes [C].

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

- Input the DTC: P0116.

- Check the DTC judgment result.





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

- 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.

- Check the DTC judgment result again [E].

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

- 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.
WIRING DIAGRAM





INSEPCTION PROCEDURE

HINT
- If DTC P0115, P0116, P0117, P0118 and P0125 are output simultaneously, ECT sensor circuit may be open or shorted. Perform the troubleshooting of DTC P0115, P0117 or P0118 first.
- Read freeze frame data using the Techstream. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, 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 OTHER DTC OUTPUT (IN ADDITION TO DTC P0116)

Result:





B -- GO TO DTC CHART Diagnostic Trouble Code Descriptions
A -- Continue to next step.

2. INSPECT THERMOSTAT

(a) Remove the thermostat Testing and Inspection.

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

OK:

Temperature value is 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

OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR