P1115

DTC P1114 or P1115

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 P1114
- Engine Coolant Temperature (ECT) Sensor Circuit Intermittent Low Voltage

DTC P1115
- Engine Coolant Temperature (ECT) Sensor Circuit Intermittent High Voltage

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 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 DTCs

* The engine has been running for greater than 2 minutes.
* The DTCs run continuously when the above condition is met.

Conditions for Setting the DTC

P1114

The ECM detects that the ECT sensor is greater than 149°C (300°F ) intermittently.

P1115

The ECM detects that the ECT sensor is less than -38°C (-34°F) intermittently.

Action Taken When the DTC Sets

DTCs P1114 and P1115 are Type C DTCs.

Conditions for Clearing the MIL/DTC

DTCs P1114 and P1115 are Type C DTCs.

Reference Information
Schematic Reference

Engine Controls Schematics (Electrical Diagrams)
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 running, observe the scan tool DTC Information parameter. DTCs P0117 or P0118 should not set.

• If any DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code Descriptions).

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

Engine running, observe the scan tool engine coolant temperature (ECT) sensor parameter while moving the related wiring harness and harness connectors. The reading should not change abruptly.

If the reading changes abruptly, repair the wiring harness and harness connectors.

Component Testing

1. Ignition OFF, disconnect the harness connector at the ECT sensor.

Important: A thermometer can be used to the 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 (Service and Repair)
* Control Module References (Programming and Relearning)for engine control module replacement, setup, and programming