Dtc P0115 Engine Coolant Temperature Circuit Malfunction
DESCRIPTION
MONITOR DESCRIPTION
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
WIRING DIAGRAM
INSPECTION PROCEDURE
READ VALUE USING TECHSTREAM (ENGINE COOLANT TEMPERATURE)
READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS)
CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)
READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS)
CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM)
DTC P0115 Engine Coolant Temperature Circuit Malfunction |
DTC P0117 Engine Coolant Temperature Circuit Low Input |
DTC P0118 Engine Coolant Temperature Circuit High Input |
DESCRIPTION
A thermistor is built into the Engine Coolant Temperature (ECT) sensor, of which the resistance value varies according to the ECT.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 any of DTCs P0115, P0117 and P0118 are stored, 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.
DTC No.
| DTC Detection Condition
| Trouble Area
|
P0115
| Open or short in ECT sensor circuit for 0.5 seconds (1 trip detection logic)
| - Open or short in ECT sensor circuit
- ECT sensor
- ECM
|
P0117
| Short in ECT sensor circuit for 0.5 seconds (1 trip detection logic)
| - Short in ECT sensor circuit
- ECT sensor
- ECM
|
P0118
| Open in ECT sensor circuit for 0.5 seconds (1 trip detection logic)
| - Open in ECT sensor circuit
- ECT sensor
- ECM
|
- HINT:
- When any of these DTCs are output, check the ECT by entering the following menus on the Techstream: Powertrain / Engine and ECT / Data List / Coolant Temp.
Temperature Displayed
| Malfunction
|
-40°C (-40°F)
| Open circuit
|
135°C (275°F) or higher
| Short circuit
|
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 stores 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 stores 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 stores DTC P0117.If the malfunction is not repaired successfully, a DTC is stored 0.5 seconds after the engine is next started.
MONITOR STRATEGY
Related DTCs
| P0115: ECT sensor range check (Fluctuating) P0117: ECT sensor range check (Low voltage) P0118: ECT sensor range check (High voltage)
|
Required Sensors/Components (Main)
| ECT sensor
|
Required Sensors/Components (Related)
| -
|
Frequency of Operation
| Continuous
|
Duration
| 0.5 seconds
|
MIL Operation
| Immediate
|
Sequence of Operation
| None
|
TYPICAL ENABLING CONDITIONS
Monitor runs whenever following DTCs not present
| None
|
TYPICAL MALFUNCTION THRESHOLDS
P0115:ECT sensor voltage
| Less than 0.14 V [More than 135°C (275°F)], or more than 4.91 V [Less than -60°C (-76°F)]
|
P0117:ECT sensor voltage [ECT]
| Less than 0.14 V [More than 135°C (275°F)]
|
P0118:ECT sensor voltage [ECT]
| More than 4.91 V [Less than -60°C (-76°F)]
|
COMPONENT OPERATING RANGE
ECT sensor voltage [ECT]
| 0.14 to 4.91 V [-60°C to 135°C (-76°F to 275°F)]
|
CONFIRMATION DRIVING PATTERN
- Connect the Techstream to the DLC3.
- Turn the ignition switch to ON and turn the Techstream on.
- 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.
- Wait 0.5 seconds or more.
- Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
- Read 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 and ECT / Utility / All Readiness.
- Input the DTC: P0115, P0117 or P0118.
- 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 test result is INCOMPLETE or N/A and no pending DTC is output, perform a universal trip and check for permanent DTCs (YARIS_NCP93 RM000000PDK0QGX.html).
- HINT:
- If a permanent DTC is output, the system is malfunctioning.
- If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
INSPECTION PROCEDURE
- HINT:
- 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.
- If DTC P0117 is stored, check that the engine does not overheat (the DTC P0117 may be stored due to engine overheating).
1.READ VALUE USING TECHSTREAM (ENGINE COOLANT TEMPERATURE) |
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
Read the value displayed on the Techstream.
- Standard Value:
- 80°C to 100°C (167°F to 212°F) with warm engine.
ResultTemperature Displayed
| Proceed To
|
-40°C (-40°F)
| A
|
135°C (275°F) or higher
| B
|
80°C to 100°C (167°F to 212°F)
| C
|
- HINT:
- If there is an open circuit, the Techstream indicates -40°C (-40°F).
- If there is a short circuit, the Techstream indicates 135°C (275°F) or higher.
2.READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) |
Disconnect the C19 Engine Coolant Temperature (ECT) sensor connector.
Connect terminals 1 and 2 of the ECT sensor connector on the wire harness side.
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
Read the value displayed on the Techstream.
- Standard Value:
- 135°C (275°F) or higher.
Reconnect the ECT sensor connector.
3.CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM) |
Disconnect the C19 ECT sensor connector.
Disconnect the C20 ECM connector.
Check the resistance.
- Standard resistance:
Tester Connections
| Specified Conditions
|
THW (C19-2) - THW (C20-97)
| Below 1 Ω
|
E2 (C19-1) - ETHW (C20-96)
|
Reconnect the ECT sensor connector.
Reconnect the ECM connector.
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|
4.READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) |
Disconnect the C19 ECT sensor connector.
Connect the Techstream to the DLC3.
Turn the ignition switch to ON.
Turn the Techstream on.
Enter the following menus: Powertrain / Engine and ECT / Data List / Coolant Temp.
Read the value displayed on the Techstream.
- Standard Value:
- -40°C (-40°F)
Reconnect the ECT sensor connector.
5.CHECK HARNESS AND CONNECTOR (ENGINE COOLANT TEMPERATURE SENSOR - ECM) |
Disconnect the C19 ECT sensor connector.
Disconnect the C20 ECM connector.
Check the resistance.
- Standard resistance:
Tester Connections
| Specified Conditions
|
THW (C19-2) or THW (C20-97) - Body ground
| 10 kΩ or higher
|
Reconnect the ECT sensor connector.
Reconnect the ECM connector.
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|