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DTC P0116-00: Engine coolant temperature sensor circuit performance
 
 
 
 
CIRCUIT OPERATION
  • A power voltage of 5 volts is applied to the engine coolant temperature sensor connector terminal number 1 from the ECM connector terminal number 38.
  • The power voltage is grounded to the ECM connector terminal number 28 from the engine coolant temperature sensor connector terminal number 2.
  • 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 resistance decreases.
  • The engine coolant temperature sensor output voltage increases when the resistance increases and decreases when the resistance decreases.
 
 
TECHNICAL DESCRIPTION
  • The engine coolant temperature sensor converts the engine coolant temperature to a voltage and outputs it.
  • The ECM checks whether this voltage is within a specified range.
 
 
DESCRIPTIONS OF MONITOR METHODS
Engine coolant temperature sensor output voltage does not change for specified period when engine coolant temperature sensor output voltage at engine start is over 7°C (45°F).
 
 
MONITOR EXECUTION
Once per driving cycle.
 
 
MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
Other Monitor (There is no temporary DTC set in memory for the item monitored below)
  • Not applicable
Sensor (The sensor below is determined to be normal)
  • Mass airflow sensor
  • Intake air temperature sensor
 
 
DTC SET CONDITIONS
Logic Flow Chart
 
 
Check Conditions
  • Engine coolant temperature was 8°C (46°F) or higher when the engine started.
  • 12V starter battery positive voltage is 10 volts or higher.
  • The accumulation is more than 300 seconds during the acceleration having the mass airflow rate of 12 g/sec (0.42 oz./sec) or more.
  • The accumulation is more than 30 seconds during the deceleration having the mass airflow rate of 9 g/sec (0.317 oz./sec) or less.
  • Intake air temperature is lower than –10°C (14°F), or higher than 60°C (140°F).
  • However, time is not counted when fuel is shut off.
Judgment Criteria
  • Engine coolant temperature fluctuates within 1°C (1.8°F) after 330 seconds have passed since the engine was started, when the engine coolant temperature at engine start is 60°C (140°F) or higher.
  • Engine coolant temperature fluctuates within 3°C (5.4°F) after 330 seconds have passed since the engine was started, when the engine coolant temperature at engine start is lower than 60°C (140°F).
 
 
FAIL-SAFE AND BACKUP FUNCTION
None.
 
 
OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function, OBD-II Drive Cycle – Pattern 2 OBD- II DRIVE CYCLE.
 
 
TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
  • Engine coolant temperature sensor failed.
  • Engine coolant temperature sensor circuit harness damage or connector damage.
  • ECM failed.
 
 
DIAGNOSIS
Required Special Tools:
  • MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
  • MB992745: V.C.I.-Lite main harness A
  • MB992747: V.C.I.-Lite USB cable short
  • MB992748: V.C.I.-Lite USB cable long
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. Check engine coolant temperature sensor itself.
Check engine coolant temperature sensor itself (Refer to ENGINE COOLANT TEMPERATURE SENSOR CHECK).
Q: Is the check result normal?
Replace the engine coolant temperature sensor (Refer to ENGINE, Engine Cooling – Water Hose and Water Pipe WATER HOSE AND WATER PIPE REMOVAL AND INSTALLATION).
 
3.STEP 3. 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?
 
4.STEP 4. 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.
 
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 short circuit and damage.
Q: Is the check result normal?
Repair or replace the connector, or repair the damaged harness wire.
 
6.STEP 6. 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?
Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION).
 
7.STEP 7. 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 P0116-00 set?
Replace the ECM (Refer to ENGINE CONTROL MODULE (ECM) REMOVAL AND INSTALLATION).
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).