Volt

DTC P0117, P0118, or P0119

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 intermitten circuit condition between the ECM and ECT sensor.

P0117

P0118

P0119

P0117

The ECM detects that the ECT sensor signal is warmer than 149°C (300°F) for greater than 5 s.

P0118

Note: The scan tool display range is between -40°C to +150°C (-40°F to +302°F).

The ECM detects that the ECT sensor signal is colder than -59°C (-74°F) for greater than 5 s.

P0119

The ECM detects that the ECT sensor signal has abruptly changed by a minimum of 5°C (9°F), warmer or colder for greater than 3 s.

DTCs P0117, P0118 and P0119 are Type B DTCs

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Cooling System Description and Operation

Hybrid Modes of Operation Description

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Engine running, observe the scan tool ECT Sensor parameter. The reading should be between -39 to +139°C (-38 to +282°F).
2. Engine running, observe the scan tool 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 or the harness connectors.

3. 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.

1. Vehicle OFF, disconnect the harness connector at the B34 engine coolant temperature sensor.
2. Vehicle OFF, all systems OFF. This may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 Ω 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 K20 engine control module.

3. Vehicle in Service Mode, verify the scan tool ECT Sensor is colder than -39°C (-38.2°F).

⇒	If warmer than the specified range, test the signal circuit terminal 2 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 2 and the low reference circuit terminal 2. Verify the scan tool ECT Sensor is warmer than 140°C (284°F).

⇒	If colder 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.

Static Test

1. Vehicle OFF, remove the B34 engine coolant temperature sensor.

Note: A thermometer can be used to test the sensor off the vehicle.

2. Test the B34 engine coolant temperature 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% of the specification.

⇒	If not within the specified range, replace the B34 engine coolant temperature sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.