Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provide an overview of each diagnostic category. |
DTC Descriptor
DTC P0119: Engine Coolant Temperature (ECT) Sensor Circuit IntermittentDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
ECT Sensor Signal | P0117, P0119 | P0118, P0119 | P0118¹, P0119¹ | P0116 |
Low Reference | -- | P0118, P0119 | P0118¹, P0119¹ | P0116 |
¹ Internal ECM or ECT sensor damage may occur if the circuit is shorted to B+. | ||||
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Engine operating in Closed Loop. Parameter Normal Range: Varies with ambient temperature and engine operation. | |||
ECT Sensor Signal | 0 Volts | 5 Volts | 5 Volts¹ |
Low Reference | -- | 5 Volts | 5 Volts¹ |
¹ Internal ECM or ECT sensor damage may occur if the circuit is shorted to B+. | |||
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 following table illustrates the difference between temperature, resistance, and voltage:
Temperature | ECT Resistance | ECT Signal Voltage |
|---|---|---|
Cold | High | High |
Warm | Low | Low |
Conditions for Running the DTC
| • | The ignition is ON. |
| • | The ignition voltage is greater than 10 volts. |
| • | DTC P0119 runs continuously once the above condition is met. |
Conditions for Setting the DTC
The difference between the calculated ECT and the actual ECT is greater than 5°C (9°C) for at least 10 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
| • | If the vehicle has sat overnight, the IAT sensor and the ECT sensor values should display within 3°C (6°F). |
| • | Inspect for the presence of corrosion or engine coolant in the electrical connectors of the ECT. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- Ignition ON, observe the scan tool ECT sensor parameter while moving the ECT sensor connector and the ECM connector. The reading should not fluctuate while moving the related harnesses and connectors.
- Operate the vehicle within the conditions for running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data List.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the ECT sensor.
- Verify the scan tool ECT sensor voltage parameter is at 5 volts.
- Install a 3A fused jumper wire between the signal circuit and the low reference circuit. Verify the scan tool ECT sensor voltage parameter is less than 0.5 volts.
- If all circuits test normal, test or replace the ECT sensor.
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM. |
Component Testing
- Ignition OFF, disconnect the harness connector at the ECT sensor.
- Test the sensor by varying the sensor temperature while monitoring the sensor resistance.
- Compare the readings with the Temperature Versus Resistance table and verify that the resistance is within 5 percent of the specification.
Important: A thermometer can be used to test the sensor off the vehicle.
| ⇒ | If not within the specified range, replace the ECT sensor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for engine control module replacement, setup, and programming |
