Coolant Temperature Sensor (CTS)
If a coolant sensor related code is present, see appropriate G - TESTS W/ CODES article.
An out-of-calibration sensor may not set a trouble code. Use following procedure to test sensor calibration. Disconnect coolant temperature sensor connector. Measure resistance between sensor terminals. Resistance should be high when engine is cold and drop as engine warms. See CTS RESISTANCE VALUES table.
CTS RESISTANCE VALUES
| Temperature °F (°C) | Resistance Ohms |
|---|---|
| 210 (100) | 185 |
| 160 (70) | 450 |
| 100 (38) | 1800 |
| 70 (20) | 3400 |
| 20 (-7) | 13,500 |
| 0 (-18) | 25,000 |
| -40 (-40) | 100,700 |