An engine coolant temperature circuit short to ground can cause the vehicle to overheat. This is because the sensor uses a variable resistance to adjust the amount of fuel injected into the engine, and when it is shorted to ground, it will cause the engine to run too rich and overheat.
Symptoms
The following are some of the symptoms of an engine coolant temperature circuit short to ground:
- The engine overheats
- The check engine light is illuminated
- The coolant temperature gauge reads higher than normal
Diagnosis
To diagnose an engine coolant temperature circuit short to ground, you will need a multimeter.
1. Disconnect the connector for the coolant temperature sensor.
2. Set the multimeter to read ohms.
3. Connect one lead of the multimeter to the positive terminal on the coolant temperature sensor.
4. Connect the other lead of the multimeter to the ground terminal on the sensor.
5. If the multimeter reads 0 ohms, there is a short to ground in the circuit.
Repair
To repair an engine coolant temperature circuit short to ground, you will need to find and repair the damaged wire or connection.
- The damaged wire or connection may be located in the harness or near the sensor itself.
- Once you have found the damaged wire, you will need to repair or replace it.
- After the repair is complete, reconnect the connector for the coolant temperature sensor.
- The vehicle should then be retested to make sure the repair is complete.
