Engine Coolant Temperature Circuit Range / Performance Problem (P0116)

DESCRIPTION

Refer to DTC P0115 (See page ).

DTC No.	DTC Detection Condition	Trouble Area
P0116	When either of the following conditions is met (2 trip detection logic). During engine warm up after cold engine starts, change in engine coolant temperature sensor output is below threshold In duration between warmed engine stopped and next cold engine starts, change in engine coolant temperature sensor output below threshold	Thermostat Engine coolant temperature sensor

MONITOR DESCRIPTION Engine Coolant Temperature Sensor Cold Start Monitor

The monitor runs when the engine is started cold. If the change in engine coolant temperature sensor output until the engine is 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 is illuminated and the DTC is stored.

Engine Coolant Temperature Sensor Soak Monitor

The ECM compares the engine coolant temperature when the fully warmed up 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 stored.

MONITOR STRATEGY

Related DTCs	P0116: Engine Coolant Temperature Sensor Cold Start Monitor P0116: Engine Coolant Temperature Sensor Soak Monitor
Required Sensors/Components (Main)	Engine coolant temperature sensor
Required Sensors/Components (Related)	None
Frequency of Operation	Once per driving cycle
Duration	-: Cold start monitor 10 seconds: Soak monitor
MIL Operation	2 driving cycles
Sequence of Operation	None

TYPICAL ENABLING CONDITIONS All

Monitor runs whenever the following DTCs are not stored

None

Engine Coolant Temperature Sensor Cold Start Monitor

All of the following conditions are met	-
Battery voltage	10.5 V or higher
Time after engine start	1 second or more
Engine coolant temperature at engine start	Below 60 °C
Engine coolant temperature sensor circuit fail (P0115, P0117, P0118, P0125)	Not detected
Intake air temperature sensor circuit fail (P0112, P0113)	Not detected
Thermostat fail (P0128)	Not detected
Soak time	0 seconds or more
Accumulated mass air flow	4774 g or more
Fuel cut	OFF
Difference between engine coolant temperature at engine start and intake air temperature	Below 40 °C

Engine Coolant Temperature Sensor Soak Monitor

All of the following conditions are met	-
Battery voltage	10.5 V or higher
Engine	Running
Engine coolant temperature sensor circuit fail (P0115, P0117, P0118, P0125)	Not detected
Intake air temperature sensor circuit fail (P0112, P0113)	Not detected
Thermostat fail (P0128)	Not detected
Soak time fail (P2610)	Not detected
Soak time	5 hours or more
Either of the following conditions is met	(a) or (b)
(a) Engine coolant temperature	60 °C or higher
(b) Accumulated mass air flow	9549 g or more

TYPICAL MALFUNCTION THRESHOLDS Engine Coolant Temperature Sensor Cold Start Monitor

Engine coolant temperature sensor value change

Below 5 °C

Engine Coolant Temperature Sensor Soak Monitor

Difference between current engine coolant temperature sensor value and previous engine coolant temperature sensor value when engine stopped

Below 5 °C (Varies with engine coolant temperature of last trip engine stop)

COMPONENT OPERATING RANGE

Engine coolant temperature

Engine coolant temperature sensor value changes in accordance with actual engine coolant temperature

CONFIRMATION DRIVING PATTERN

1. 1
   Connect the Techstream to the DLC3.
2. 2
   Turn the ignition switch to ON and turn the Techstream on.
3. 3
   Enter the following menus: Powertrain / Engine / Data List / Coolant Temp.
4. 4
   Check that the engine coolant temperature is 60 °C or less.
5. 5
   Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure) (See page ).
6. 6
   Turn the ignition switch off and wait for at least 30 seconds.
7. 7
   Turn the ignition switch to ON and turn the Techstream on [A].
8. 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 or higher, the engine coolant temperature sensor is malfunctioning. It is not necessary to continue this procedure.

9. 9
   Enter the following menus: Powertrain / Engine / Trouble Codes [C].
10. 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. 11
    Enter the following menus: Powertrain / Engine / Utility / All Readiness.
12. 12
    Input the DTC: P0116.
13. 13
    Check the DTC judgment result.

    Techstream Display	Description
    NORMAL	DTC judgment completed System normal
    ABNORMAL	DTC judgment completed System abnormal
    INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
    N/A	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • If the judgment result shows INCOMPLETE or N/A, perform steps [D] and [E].
14. 14
    Drive the vehicle at 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.

15. 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. 16
    If no pending DTC is output, perform a universal trip and check for permanent DTCs (See page ).
    

    HINT:

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

CAUTION / NOTICE / HINT

HINT:

• If any of DTCs P0115, P0117, P0118 or P0125 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 / Primary / 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 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 / Trouble Codes.

(e) Read the DTCs.

Result	Proceed to
DTC P0116 is output	A
DTC P0116 and other DTCs are output	B

HINT:

If any DTCs and other than P0116 are output, troubleshoot those DTCs first.

B

GO TO DTC CHART

A

1. INSPECT THERMOSTAT

(a) Inspect the thermostat (See page ).

HINT:

Perform "Inspection After Repair" after replacing the engine coolant temperature sensor (See page ).

OK

REPLACE ENGINE COOLANT TEMPERATURE SENSOR

NG

REPLACE THERMOSTAT