P0117
DTC P0117, P0118, or P0119
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions 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
DTC P0119
- Engine Coolant Temperature (ECT) Sensor Circuit Intermittent
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The engine coolant temperature (ECT) sensor is a variable resistor that measures the temperature of the engine coolant. The engine control module (ECM) supplies 5 V to the ECT sensor signal circuit and a ground for the low reference circuit. This diagnostic checks for an open, short to ground or an intermittent circuit condition between the ECM and ECT sensor.
Conditions for Running the DTCs
* The ignition is ON or the engine is running.
* These DTCs run continuously within the enabling conditions.
Conditions for Setting the DTC
P0117
The ECM detects that the ECT is warmer than 142°C (288°F) for greater than 4 seconds.
P0118
The ECM detects that the ECT is colder than -39°C (-38°F) for greater than 4 seconds.
P0119
The ECM detects that the ECT is intermittent or has abruptly changed for greater than 4 seconds.
Action Taken When the DTC Sets
* DTCs P0117, P0118 and P0119 are Type B DTCs.
* The cooling fans will be commanded ON.
* The AC compressor will be commanded OFF.
Conditions for Clearing the MIL/DTC
DTCs P0117, P0118 and P0119 are Type B DTCs.
Reference Information
Schematic Reference
Engine Controls Schematics (LHU) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Sunshade - Left
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify the scan tool ECT Sensor parameter is between -39 to + 120°C (-38 to +248°F) and changes with engine run time.
• If not between -39 to + 120°C (-38 to +248°F) or does not change
Refer to Circuit/System Testing.
• If between -39 to + 120°C (-38 to +248°F) and changes
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
4. Verify the DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing.
• If the DTC does not set
5. All OK.
Circuit/System Testing
1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B34 Engine Coolant Temperature Sensor. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 5 ohms between the low reference terminal A and ground.
• If 5 ohms or greater
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for less than 2 ohms in the low reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If less than 5 ohms
3. Ignition ON.
4. Verify the scan tool ECT Sensor parameter is colder than -39°C (-38°F).
• If warmer than -39°C (-38°F)
1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
2. Test for infinite resistance between the signal circuit terminal B and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K20 Engine Control Module.
• If colder than -39°C (-38°F)
5. Install a 3 A fused jumper wire between the signal circuit terminal B and the low reference circuit terminal A.
6. Verify the scan tool ECT sensor parameter is warmer than 149°C (300°F).
• If colder than the 149°C (300°F)
1. Ignition OFF, remove the jumper wire, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V
3. Ignition OFF
4. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K20 Engine Control Module.
• If warmer than 149°C (300°F)
7. Test or replace the B34 Engine Coolant Temperature Sensor.
Component Testing
1. Ignition OFF, disconnect the harness connector at the B34 Engine Coolant Temperature Sensor.
2. Test the ECT sensor by varying the sensor temperature while monitoring the sensor resistance. Compare the readings with the Temperature Versus Resistance (ECT) Temperature Versus Resistance (ECT) table. The resistance values should be in range of the table values.
• If not within the specified range
• Replace the B34 Engine Coolant Temperature Sensor.
• If within the specified range
3. Test for infinite resistance between each terminal and the sensor housing.
• If less than infinite resistance
Replace the B34 Engine Coolant Temperature Sensor.
• If infinite resistance
4. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Engine Coolant Temperature Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, setup, and programming