P0116
Fuel System - Troubleshooting - P0116Component Location:
GENERAL DESCRIPTION
An Engine Coolant Temperature Sensor (ECTS) monitors the temperature of the coolant. This input is used by the PCM for engine control and as an enabling criteria for same diagnostics. The air flow coming into the engine is accumulated and used to determine if the engine has been driven within conditions that would allow the engine coolant to heat up normally to the thermostat regulating temperature. If the coolant temperature does not reach regulating temperature of the thermostat, diagnostics that use engine coolant temperature as enabling criteria, may not run when expected. This DTC will set when there has been excessive time to reach a minimum coolant temperature required for closed loop fuel control.
DTC DESCRIPTION
The purpose of this diagnosis is to detect a stuck coolant temperature signal. The diagnostic function checks whether after a variation of the calculated coolant temperature also a variation of the measured coolant temperature is detected. PCM sets DTC P0116 when the variation of measured engine coolant temperature from engine start is smaller than threshold while variation of calculated coolant temperature by PCM is greater than threshold.
DTC Detecting Condition:
MONITOR DTC STATUS
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F5(INFO) to select DTC information from the DTCs menu.
3. Confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Read "DTC Status" parameter.
5. Is parameter displayed "History(Not Present) fault"?
NOTE:
1. History (Not Present) fault : DTC occurred but has been cleared.
2. Present fault : DTC is occurring at present time.
YES - Fault is intermittent caused by poor contact in the sensor's and/or the PCM's connector, which was repaired but PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO - Go to "Cooling system inspection" procedure.
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES - Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO- Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure
COOLING SYSTEM INSPECTION
1. Check cooling system coolant level and fill if low.
2. Check for a proper cooling system operation. Especially check that cooling and condenser fan working normally.
3. Remove the thermostat and check the following items:
- Stuck or damaged
- Verify the temperature at which the valve begins to open.
A. Valve opening temperature : 82 degrees C (179.6 degrees F)
B. Valve opening temperature : 95 degrees C (203 degrees F)
4. is a problem found?
YES - Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO - Go to "Terminal and Connector Inspection" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scan tool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Press F5(INFO) and confirm that "DTC Readiness Flag" indicates "Complete". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions.
3. Read "DTC Status" parameter.
4. Is parameter displayed "History(Not Present) fault"?
YES - System performing to specification at this time. Clear the DTC
NO - Go to the applicable troubleshooting procedure.
Schematic Diagram:
