With Variable Camshaft Phasing
DTC P0117 or P0118
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0117
- Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage
DTC P0118
- Engine Coolant Temperature (ECT) Sensor Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The engine coolant temperature (ECT) sensor 1 is a variable resistor that measures the temperature of the engine coolant. The engine control module (ECM) supplies 5 volts to the ECT signal circuit and supplies a ground to the low reference circuit.
The following table illustrates the difference between temperature, resistance, and voltage:
Conditions for Running the DTC
P0117
* The ignition is ON, or the engine is operating.
* The DTC runs continuously when either of the above conditions are met.
P0118
* The engine run time is greater than 10 seconds.
* The intake air temperature (IAT) sensor is greater than 0°C (32°F).
* The DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
P0117
The ECM detects that the ECT sensor is greater than 149°C (300°F).
Note: The scan tool only displays to -40°C (-40°F).
P0118
The ECM detects that the ECT sensor is colder than -60°C (-76°F).
Action Taken When the DTC Sets
* DTC P0117 and P0118 are Type B DTCs.
* The ECM commands the cooling fans ON.
Conditions for Clearing the MIL/DTC
DTC P0117 and P0118 are Type B DTCs.
Diagnostic Aids
* The engine coolant temperature gage will display full cold when an ECT DTC sets.
* After starting the engine, the ECT sensor temperature should rise steadily, then stabilize after the thermostat opens.
* Test the ECT sensor at various temperature levels in order to evaluate the possibility of a skewed sensor. A skewed sensor can result in a driveability condition.
Reference Information
Schematic Reference
Engine Controls Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
1. Engine idling, observe the DTC information with a scan tool. DTCs P0117 or P0118 should not set.
2. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the ECT sensor 1.
2. Ignition OFF for 1 minute, test for less than 5 ohm between the low reference circuit terminal 1 and ground.
• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
3. Ignition ON, verify the scan tool ECT sensor parameter is at -40°C (-40°F).
• If warmer than the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the ECM.
Note: If the fuse in the jumper wire opens, the signal circuit is shorted to a voltage and the sensor may be damaged.
4. Install a 1 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool ECT sensor parameter is greater than 149°C (300°F).
• If less than specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
5. If all circuits test normal, test or replace the ECT sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the ECT sensor.
Note: A thermometer can be used to test the sensor off the vehicle.
2. Test the ECT sensor by varying the sensor temperature while monitoring the sensor resistance. Compare the readings with the Temperature Versus Resistance (Temperature Versus Resistance) table and verify that the resistance is within 5 percent of the specification.
• If not within the specified range, replace the ECT sensor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Engine Coolant Temperature Sensor Replacement (ECT 1) (Service and Repair)Engine Coolant Temperature Sensor Replacement (ECT 2) (Service and Repair)
* Control Module References (Programming and Relearning) for ECM replacement, setup, and programming