1.STEP 1. Using scan tool (M.U.T.-III SE), check the data list.
Use scan tool (M.U.T.-III SE) to check the data list (Refer to DATA LIST REFERENCE TABLE).- Item number 60: Coolant (Water) Temperature Sensor
Q: Is the check result normal?
2.STEP 2. Perform voltage measurement at engine coolant temperature sensor connector terminal number 1.
- Disconnect connector, and connect the test harness special tool MB991658 between the separated connectors.
- Power supply mode of electric motor switch: ON
- Voltage between engine coolant temperature sensor connector terminal number 1 and ground.
OK
- When engine coolant temperature is –20°C (–4°F), voltage should be between 3.9 and 4.5 volts.
- When engine coolant temperature is 0°C (32°F), voltage should be between 3.2 and 3.8 volts.
- When engine coolant temperature is 20°C (68°F), voltage should be between 2.3 and 2.9 volts.
- When engine coolant temperature is 40°C (104°F), voltage should be between 1.3 and 1.9 volts.
- When engine coolant temperature is 60°C (140°F), voltage should be between 0.7 and 1.3 volts.
- When engine coolant temperature is 80°C (176°F), voltage should be between 0.3 and 0.9 volt.
Q: Is the check result normal?
3.STEP 3. Using scan tool (M.U.T.-III SE), check the data list.
Use scan tool (M.U.T.-III SE) to check the data list (Refer to DATA LIST REFERENCE TABLE).- Item number 60: Coolant (Water) Temperature Sensor
Q: Is the check result normal?
4.STEP 4. Perform voltage measurement at engine coolant temperature sensor connector terminal number 1.
- Disconnect connector, and measure at harness side.
- Power supply mode of electric motor switch: ON
- Voltage between engine coolant temperature sensor connector terminal number 1 and ground.
OK: 4.9 to 5.1 volts
Q: Is the check result normal?
5.STEP 5. Check harness between engine coolant temperature sensor connector terminal number 1 and ECM connector terminal number 38.
Check power supply line for damage.Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
6.STEP 6. Perform resistance measurement at engine coolant temperature sensor connector terminal number 2.
- Disconnect connector, and measure at harness side.
- Resistance between engine coolant temperature sensor connector terminal number 2 and ground.
OK: Continuity (2 ohms or less)
Q: Is the check result normal?
7.STEP 7. Check harness between engine coolant temperature sensor connector terminal number 2 and ECM connector terminal number 28.
Check ground line for open circuit and damage.Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
8.STEP 8. Check engine coolant temperature sensor itself.
9.STEP 9. Test the OBD-II drive cycle.
After erasing the DTC, carry out test drive with the drive cycle pattern, and recheck the DTC.(1) Use scan tool (M.U.T.-III SE) to erase the DTC.
(2) Carry out test drive with the drive cycle pattern (Refer to Diagnostic Function, OBD-II Drive Cycle – Pattern 2 OBD- II DRIVE CYCLE). (3) Use scan tool (M.U.T.-III SE) to recheck the DTC.
Q: Is DTC P0125-00 set?
Intermittent malfunction (Refer to GENERAL INFORMATION, General Information – How to Use Troubleshooting/Inspection Service Points – How to Cope with Intermittent Malfunctions HOW TO COPE WITH INTERMITTENT MALFUNCTIONS).