General Motors DTC P0117, DTC P0118 User Manual

DTC P0117

DTC P0118

2013 Chevrolet Silverado - 4WD | Cheyenne, Sierra, Silverado VIN C/K Service Manual 3087 | Engine |

Engine Controls/Fuel - 6.6L LGH or LML | Diagnostic Information and Procedures | Document ID: 2442645

DTC P0117 or P0118

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 provides an overview of each diagnostic category.

DTC Descriptors

Engine Coolant Temperature (ECT) Sensor Circuit Low Voltage

Engine Coolant Temperature (ECT) Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to

Ground

Open/High

Resistance

Short to

Voltage

Signal

Performance

ECT Sensor Signal P0117 P0118 P0118 P0128

Low Reference — P0118 P0118 P0128

Typical Scan Tool Data

ECT Sensor Temperature

Circuit

Short to

Ground Open

Short to

Voltage

Operating Conditions: Engine Running
Parameter Normal Range: −39 to 149°C (−38 to 300°F)

ECT Sensor Signal 150°C (302°F) −40°C (−40°F) −40°C (−40°F)

Low Reference — −40°C (−40°F) −40°C (−40°F)

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 DTC

P0117 or P0118

DTCs P0106, P0191, P0234, P0263, P0266, P0269, P0272, P0275, P0278, P0281, P0284,
P0299, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0401, P0402,

P0506, P0507, P2080, P2084, P242B or P246F are not set.

The ignition is ON.

Battery voltage is greater than 11 V.

The DTCs run continuously when the above conditions are met.

Conditions for Setting the DTC

P0117

The ECM detects that the ECT Sensor is warmer than 149°C (300°F) for greater than 15 s.

P0118

The ECT sensor temperature is colder than −39°C (−38°F) for greater than 60 s.

Action Taken When the DTC Sets

DTCs P0117 and P0118 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P0117 and P0118 are Type A DTCs.

Diagnostic Aids

DTC P0128 occurring with insufficient vehicle interior heating is an indication of improper
thermostat operation.

Inspect the ECT sensor terminals and the ECT harness connector for corrosion. This condition
results in a greater voltage on the ECT sensor signal circuit, which is interpreted by the ECM
as a colder ECT.

A slight to moderate resistance in the ECT sensor signal circuit or low reference circuit will
affect this diagnostic. This condition results in a greater voltage on the ECT sensor signal
circuit, which is interpreted by the ECM as a colder ECT.

Reference Information

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

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