For 1990-2009 cars

### Test Description

The number below refers to the step number on the diagnostic table.

1. Begin the diagnostic table at Step 1 if the problem is that the temperature gage always indicates HOT. Begin the diagnostic table at Step 7 if the problem is that the temperature gage always indicates COOL.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
1 | Allow the engine to cool to room temperature. With the ignition ON, does the temperature gage always read at the high end of the scale? | -- | Go to Step 2 | Go to Step 7
2 | Disconnect the coolant temperature sensor electrical connector. Does the temperature gage indicator drop to the low end of the scale? | -- | Go to Step 3 | Go to Step 4
3 | Replace the coolant temperature gage sensor. Refer to Engine Coolant Temperature Sensor Replacement . Is the repair complete? | -- | System OK | --
4 | Inspect for a short to ground between the coolant temperature sensor and the temperature gage. | -- | Go to Step 5 | Go to Step 6
5 | Repair the short to ground. Is the repair complete? | -- | System OK | --
6 | Replace the instrument cluster. Refer to Instrument Cluster Replacement . Is the repair complete? | -- | System OK | --
7 |

1. Disconnect the coolant temperature sensor.
2. Turn on the ignition, with the engine OFF.
3. Measure the voltage at the coolant temperature sensor connector.

Is the voltage within the specified range?

11-14 V

Go to Step 10

Go to Step 8

8 | Inspect for an open circuit between the coolant temperature sensor and the temperature gage. Is there an open circuit? | -- | Go to Step 9 | Go to Step 6
9 | Repair the open circuit between the coolant temperature sensor and the temperature gage. Is the repair complete? | -- | System OK | --
10 |

1. Disconnect the coolant temperature sensor.
2. Connect a jumper wire between the coolant temperature sensor connector and ground.
3. Turn on the ignition, with the engine OFF.

Does the temperature gage move to the high end of the scale?

--

Go to Step 3

Go to Step 6