Diagnostic Aids
DTC indicates lower than normal engine coolant temperature, which most likely was not caused by a short/open or intermittent short/open in ECT wiring.
Possible causes of low engine coolant temperature:
- Thermostat is stuck open.
- Cooling fan(s) are always on.
- Very low ambient temperatures.
- Corrosion in connector or resistance in wiring.
- Skewed sensor.
ECT sensor reading may be compared to IAT sensor reading on scan tool after vehicle has been sitting more than 6 hours with ignition off. Both readings should be within 10°F (6°C) of each other.
For resistance values, see TEMPERATURE VS RESISTANCE table.
TEMPERATURE VS RESISTANCE
| °F (°C) | Ohms |
|---|---|
| 212 (100) | 177 |
| 176 (80) | 332 |
| 140 (60) | 667 |
| 104 (40) | 1459 |
| 86 (30) | 2238 |
| 68 (20) | 3520 |
| 32 (0) | 9420 |
| -4 (-20) | 28,690 |
| -40 (-40) | 100,700 |