P0119
DTC 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 Descriptor
DTC P0119
- Engine Coolant Temperature (ECT) Sensor Circuit Intermittent
Diagnostic Fault Information
Typical Scan Tool Data
Circuit 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 volts to the ECT signal circuit and supplies a ground to the low reference circuit. The ECM monitors the performance of the ECT sensor. If the ECM detects excessive noise or rapid fluctuations in the ECT signal, this DTC sets.
The following table illustrates the difference between temperature, resistance, and voltage:
Conditions for Running the DTC
* DTC P0117 or P0118 is not set.
* The ignition is ON or the engine is operating.
* DTC P0119 runs continuously once the above conditions are met.
Conditions for Setting the DTC
* The ECM detects an abrupt ECT positive temperature change or negative temperature change ±10°C (±18°F) greater than the expected value.
* The condition exists for approximately 4-6 seconds.
Action Taken When the DTC Sets
DTC P0119 is a Type B DTC.
Conditions for Clearing the MIL/DTC
DTC P0119 is a Type B DTC.
Diagnostic Aids
* 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 DTC or a driveability condition. Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor Temperature Versus Resistance - Engine Coolant Temperature Sensor.
* If the vehicle has sat overnight, the IAT sensor and the ECT sensor values should display within 5°C (41°F).
* After starting a cold engine, the ECT sensor temperature should rise steadily, then stabilize after the thermostat opens.
* Intermittent High resistance on either the ECT sensor signal circuit or the ECT sensor low reference circuit could set a DTC.
Reference Information
Schematic Reference
Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views A/C Compressor Clutch
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. Observe the scan tool engine coolant temperature (ECT) sensor parameter, while moving the ECT sensor connector and the K20 ECM connector. The ECT sensor parameter should not fluctuate while moving the related harnesses and connectors.
• Repair the suspected harness or connection if the ECT parameter fluctuates greater than 3°C (5°F) while moving the related harnesses and connectors.
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 B34 engine coolant temperature sensor.
2. Ignition OFF, all vehicle systems OFF, this may take up to 2 minutes, test for less than 5 ohms between the low reference circuit terminal A 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 K20 engine control module.
3. Ignition ON, verify the scan tool ECT Sensor parameter is colder than -40°C (-40°F).
• If warmer than the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K20 engine control module.
4. Install a 3 A fused jumper wire between the signal circuit terminal B and the low reference circuit terminal A. Verify the scan tool ECT Sensor parameter is warmer than 140°C (284°F).
• If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 engine control module.
5. If all circuits test normal, 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.
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 - Engine Coolant Temperature Sensor Temperature Versus Resistance - Engine Coolant Temperature Sensor table and verify that the resistance is within 5 percent of the specification.
• If not within the specified range, replace the B34 engine coolant temperature sensor.
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