For 1990-2009 cars

### Circuit Description

The instrument panel cluster (IPC) monitors changes in the voltage caused by the changes in the resistance of the engine coolant temperature gage sensor to determine coolant temperature. As the resistance of the gage sensor decreases, the coolant temperature gage senses a smaller voltage drop across the gage sensor indicating higher coolant temperature. As the resistance of the sensor increases, the temperature gage senses a larger voltage drop across the gage sensor indicating lower coolant temperature.

### Conditions for Setting the DTC

The coolant temperature gage circuit is tested every 100 ms. DTC 014 will set when the circuit is shorted to ground or the coolant sensor is internally shorted (less than 15 ohms) for more than 8 seconds.

### Action Taken When the DTC Sets

• | Stores a DTC 014 in memory.

• | The coolant temperature gage will default to zero.

### Conditions for Clearing the DTC

• | The resistance must be greater than 15 ohms for 4 seconds to clear the fault in the next monitoring cycle.

• | Conditions for the fault are no longer present.

• | Using a scan tool.

### Diagnostic Aids

• | Use the Freeze Frame and/or Failure Records data in order to locate an intermittent condition. If you cannot duplicate the DTC, the information included in the Freeze Frame and/or Failure Records data may aid in determining the number of miles since the DTC set. The Fail Counter and Pass Counter can also aid in determining the number of ignition cycles that the diagnostic reported a pass and/or fail. Operate the vehicle within the same freeze frame conditions (RPM, engine load, vehicle speed, temperature, etc.). This will isolate when the DTC failed.

• | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. This test determines whether there is a short to ground in the engine coolant temperature signal circuit or if there is an internal IPC problem.

2. This test determines whether the short to ground is in the engine coolant temperature signal circuit or if there is an internal engine coolant temperature gauge sensor problem.

3. Clear all DTCs within the IPC after performing this diagnostic table.

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Instrument Cluster Schematics
1 | Did you perform the IPC Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Instrument Cluster
2 |

1. Disconnect the IPC connector.
2. Test the engine coolant temperature signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is a short to ground present?

Go to Step 3

Go to Step 4

3 |

1. Disconnect the engine coolant temperature gage sensor connector.
2. Turn ON the ignition switch.
3. Test the engine coolant temperature signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 6

Go to Step 5

4 | Important: Program the replacement IPC. Replace the IPC. Refer to Instrument Cluster Replacement . Did you complete the replacement? | Go to Step 6 | --
5 | Replace the engine coolant temperature gauge sensor. Refer to Engine Coolant Temperature Sensor Replacement in Engine Controls. Did you complete the replacement? | Go to Step 6 | --
6 |

1. Use the scan tool in order to clear the IPC DTCs.
2. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2