P0117
2UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0115,P0117,P0118: Engine Coolant Temperature Circuit Malfunction
DESCRIPTION
A thermistor, whose resistance value varies according to the ECT, is built into the Engine Coolant Temperature (ECT) sensor.
The structure of the sensor and its connection to the ECM are the same as those of the Intake Air Temperature (IAT) sensor.
HINT
When DTC P0115, P0117 or P0118 is set, the ECM enters fail-safe mode. During fail-safe mode, the ECT is estimated to be 80°C (176°F) by the ECM. Fail-safe mode continues until a pass condition is detected.
HINT
When any of these DTCs are set, check the ECT by entering the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
MONITOR DESCRIPTION
- The Engine Coolant Temperature (ECT) sensor is used to monitor the ECT. The ECT sensor has a thermistor with a resistance that varies according to 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 drops. These 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 ECT. 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.
- Example:
- If the sensor output voltage is more than 4.91 V for 0.5 seconds or more, the ECM determines that there is an open in the ECT sensor circuit, and sets DTC P0118. Conversely, if the voltage output is less than 0.14 V for 0.5 seconds or more, the ECM determines that there is a short in the sensor circuit, and sets DTC P0117.
- If the malfunction is not repaired successfully, a DTC is set 0.5 seconds after the engine is next started.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
P0115:
P0117:
P0118:
COMPONENT OPERATING RANGE
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT
- If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
- Read freeze frame data using the Techstream. Freeze frame data records the engine condition 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.
PROCEDURE
1. READ OUTPUT DTC
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG) and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(d) Read DTCs.
Result
C -- READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN SENSOR)
B -- READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN SENSOR)
A -- Continue to next step.
2. READ VALUE USING TECHSTREAM (COOLANT TEMP)
(a) Connect the Techstream to the DLC3.
(b) Put the engine in inspection mode Inspection Mode Procedure.
(c) Turn the Techstream ON.
(d) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
(e) Read the value displayed on the Techstream.
Standard:
Between 80°C and 97°C (176°F and 207°F) with warm engine.
Result
HINT
- If there is an open circuit, the Techstream indicates -40°C (-40°F).
- If there is a short circuit, the Techstream indicates 140°C (284°F) or higher.
C -- CHECK FOR INTERMITTENT PROBLEMS Check For Intermittent Problems
B -- READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN SENSOR)
A -- Continue to next step.
3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN SENSOR)
(a) Disconnect the E14 Engine Coolant Temperature (ECT) sensor connector.
(b) Connect terminals 1 and 2 of the ECT sensor connector on the wire harness side.
(c) Connect the Techstream to the DLC3.
(d) Turn the power switch on (IG).
(e) Turn the Techstream ON.
(f) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
(g) Read the value displayed on the Techstream.
Standard:
140°C (284°F) or higher
NG -- READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM)
OK -- CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal
4. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN ECM)
(a) Disconnect the E14 ECT sensor connector.
(b) Connect terminals THW and E2 of the E1 ECM connector.
HINT
Before checking, do visual and contact pressure checks on the ECM connector.
(c) Connect the Techstream to the DLC3.
(d) Turn the power switch on (IG).
(e) Turn the Techstream ON.
(f) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
(g) Read the value displayed on the Techstream.
Standard:
140°C (284°F) or higher
NG -- CONFIRM GOOD CONNECTION TO ECM. IF OK, REPLACE ECM Removal
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR
5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN SENSOR)
(a) Disconnect the E14 ECT sensor connector.
(b) Connect the Techstream to the DLC3.
(c) Turn the power switch on (IG).
(d) Turn the Techstream ON.
(e) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
(f) Read the value displayed on the Techstream.
Standard:
-40°C (-40°F)
NG -- READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN ECM)
OK -- REPLACE ENGINE COOLANT TEMPERATURE SENSOR Removal
6. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN ECM)
(a) Disconnect the E1 ECM connector.
(b) Connect the Techstream to the DLC3.
(c) Turn the power switch on (IG).
(d) Turn the Techstream ON.
(e) Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Coolant Temp.
(f) Read the value displayed on the Techstream.
Standard:
-40°C (-40°F)
NG -- REPLACE ECM Removal
OK -- REPAIR OR REPLACE HARNESS OR CONNECTOR