P0117
CIRCUIT OPERATION
- 5-volt voltage is applied to the engine coolant temperature sensor output terminal (terminal 1) from the ECM (terminal 44)
- The engine coolant temperature sensor is a negative temperature coefficient type of resistor. It has the characteristic that when the engine coolant temperature rises the resistor decreases.
- The engine coolant temperature sensor output voltage increases when the resistor increases and decreases when the resistor decreases.
TECHNICAL DESCRIPTION
- The engine coolant temperature sensor converts the engine coolant temperature to a voltage and output it.
- The ECM
DTC SET CONDITIONS
Check Conditions, Judgement Criteria
- Engine coolant temperature sensor output voltage increased from a value lower than 1.6 volts to a value higher than 1.6 volts [coolant temperature decreases from a higher than 40 °C (104 °F) temperature to a lower than 40 °C (104 °F) temperature].
- Then the engine coolant temperature sensor output voltage has continued to be 1.6 volts or higher for five minutes.
Check Conditions, Judgement Criteria
- About 60 - 300 seconds have passed for the engine coolant temperature to rise to about 7 °C (44.6 °F) after starting sequence was completed.
- However, time is not counted when volume air flow sensor average output frequency is 70 Hz or less, or fuel is shut off.
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Engine coolant temperature sensor failed.
- Open or shorted engine coolant temperature sensor circuit, or loose connector.
- ECM failed.
- PPM failed
DIAGNOSIS
Required Special Tools
MB991502: Scan Tool(MUT-II)
STEP 1. Using scan tool MB991502, check data list item 21: Engine Coolant Temperature Sensor.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK"(OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991502 to the data reading mode for item 21, Engine Coolant Temperature Sensor.
- The engine coolant temperature and temperature shown with the scan tool should approximately match.
4. Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the sensor operating properly?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points.
NO: Go to Step 2.
STEP 2. Check the sensor output voltage at engine coolant temperature sensor connector B-11 by backprobing.
1. Do not disconnect the connector B-11.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 1 and ground by backprobing.
- When intake air temperature is 0 °C (32 °F), voltage should be 3.2 and 3.8 volts.
- When intake air temperature is 20 °C (68 °F), voltage should be 2.3 and 2.9 volts.
- When intake air temperature is 40 °C (104 °F), voltage should be 1.3 and 1.9 volts.
- When intake air temperature is 80 °C (176 °F), voltage should be 0.3 and 0.9 volts.
4. Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 3.
NO: Go to Step 5.
STEP 3. Check connector B-11 at the engine coolant temperature sensor for damage.
Q: Is the connector in good condition?
YES: Go to Step 4.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 14.
STEP 4. Using scan tool MB991502, check data list item 21: Engine Coolant Temperature Sensor.
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK"(OFF) position before connecting or disconnecting scan tool MB991502.
1. Connect scan tool MB991502 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Set scan tool MB991502 to the data reading mode for item 21, Engine Coolant Temperature Sensor.
- The engine coolant temperature and temperature shown with the scan tool should approximately match.
4. Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the sensor operating properly?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points.
NO: Replace the ECM or PCM. Then go to Step 14.
STEP 5. Check connector B-11 at engine coolant temperature sensor for damage.
Q: Is the connector in good condition?
YES: Go to Step 6.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 14.
STEP 6. Check the sensor supply voltage at engine coolant temperature sensor harness side connector B-11.
1. Disconnect the connector B-11 and measure at the harness side.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 1 and ground.
- Voltage should be between 4.8 and 5.2 volts.
4. Turn the ignition switch to the "LOCK"(OFF) position.
Q: Is the voltage normal?
YES: Go to Step 8.
NO: Go to Step 9.
STEP 7. Check connector C-118 at ECM
Q: Is the connector in good condition?
YES: Replace the ECM or PCM. Then go to Step 14.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 14.
STEP 8. Check the continuity at engine coolant temperature sensor harness side connector B-11.
1. Disconnect the connector B-11 and measure at the harness side.
2. Check for the continuity between terminal 2 and ground. Should be less than 2 Ohms.
Q: Is the continuity normal?
YES: Go to Step 11.
NO: Go to Step 9.
STEP 9. Check connector C-118 at ECM
Q: Is the connector in good condition?
YES: Go to Step 10.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 14.
STEP 10. Check for harness damage between engine coolant temperature sensor connector B-11 terminal 2 and ECM connector C-118 terminal 49
Q: Is the harness wire in good condition?
YES: Replace the ECM or PCM. Then go to Step 14.
NO: Repair it. Then go to Step 14.
STEP 11. Check the engine coolant temperature sensor.
1. Disconnect the engine coolant temperature sensor connector B-11
2. Remove the engine coolant temperature sensor.
3. With the temperature sensing portion of engine coolant temperature sensor immersed in hot water, check resistance.
Standard value:
5.3 - 6.7 kOhms [at 0 °C (32 °F)]
2.3 - 3.0 kOhms [at 20 °C (68 °F)]
1.0 - 1.5 kOhms [at 40 °C (104 °F)]
0.30 - 0.42 kOhms [at 80 °C (176 °F)]
4. Apply 3M(TM) AAD part number 8731 or equivalent on the screw section of the engine coolant temperature sensor.
5. Install the engine coolant temperature sensor, and tighten to the specified torque.
Tightening torque: 29 ± 10 N.m (22 ± 7 ft-lb)
Q: Is the resistance at the standard value?
YES: Go to Step 1.2.
NO: Replace the engine coolant temperature sensor. Then go to Step 14.
STEP 12. Check connector C-118 at ECM
Q: Is the connector in good condition?
YES: Go to Step 13.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 14.
STEP 13. Check for harness damage between engine coolant temperature sensor connector B-11 terminal 1 and ECM connector C-118 terminal 44
Q: Is the harness wire in good condition?
YES: Replace the ECM or PCM. Then go to Step 14.
NO: Repair it. Then go to Step 14.
STEP 14. Test the OBD-II drive cycle.
1. Carry out a test drive with the drive cycle pattern. Refer to Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code(DTC).
Q: Is the DTC P0117 is output?
YES: Retry the troubleshooting.
NO: The inspection is complete.