GSIC - Global Service Information Center

### DTC P0116 Engine Coolant Temperature Circuit Range / Performance Problem

## for Preparation Click here

## DESCRIPTION

Refer to DTC P0115 (Click here).

DTC No. | DTC Detection Condition | Trouble Area

P0116

Case 1:
If engine coolant temperature is between 35°C (95°F) and 60°C (140°F) at engine start, and conditions (a) and (b) are met (2 trip detection logic):
(a) Vehicle is driven at varying speeds (under acceleration and deceleration)
(b) Engine coolant temperature remains within 3°C (5.4°F) of engine starting temperature
Case 2:
If engine coolant temperature is more than 60°C (140°F) at engine start, and conditions (a) and (b) are met (6 trip detection logic):
(a) Vehicle is driven at varying speeds (under acceleration and deceleration)
(b) Engine coolant temperature remains within 1°C (1.8°F) of engine starting temperature, and this is successively recorded 6 times

Engine coolant temperature sensor

## MONITOR DESCRIPTION

The Engine Coolant Temperature (ECT) sensor is used to monitor the engine coolant temperature. The ECT sensor has a thermistor that varies its resistance depending on the temperature of the engine coolant. When the coolant temperature is low, the resistance in the thermistor increases. When the temperature is high, the resistance decreases. The variations in resistance are reflected in the output voltage from the sensor. The ECM monitors the sensor voltage and uses this value to calculate the engine coolant temperature. When the sensor output voltage deviates from the normal operating range, the ECM interprets this as a fault in the ECT sensor and sets a DTC.
Examples:
Case 1: Upon starting the engine, the ECT is between 35°C (95°F) and 60°C (140°F). If, after driving for 250 seconds, the ECT still remains within 3°C (5.4°F) of the starting temperature, a DTC is set (2 trip detection logic).
Case 2: Upon starting the engine, the ECT is over 60°C (140°F). If, after driving for 250 seconds, the ECT still remains within 1°C (1.8°F) of the starting temperature, the DTC is set (6 trip detection logic).

## INSPECTION PROCEDURE

HINT:

1. If DTCs P0115, P0116, P0117, and P0118 are output simultaneously, the engine coolant temperature sensor circuit may be open or short. Perform troubleshooting on DTC P0115, P0117 or P0118 first.

1. Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions 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.

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

1. Connect the intelligent tester to the DLC3.

1. Turn the ignition switch ON and turn the intelligent tester ON.

1. Enter the following menus: Powertrain / Engine and ECT / DTC.

1. Read DTCs.

   Result:

     Display (DTC output) | Proceed to
     P0116 | A
     P0116 and other DTCs | B

| B |

GO TO RELEVANT DTC CHART

A |

REPLACE ENGINE COOLANT TEMPERATURE SENSOR