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Hi I'm Dave,here P0118 - Engine Coolant Temperature Circuit High InputPossible causes - Low engine coolant level - Engine Coolant Temperature (ECT) sensor harness is open or shorted - Engine Coolant Temperature (ECT) sensor electrical circuit poor connection - Faulty Engine Coolant Temperature (ECT) sensor - Faulty engine coolant thermostat P0118 Description The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module. The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature.
ok, let me check. there might be 2 sensors. 1 for the gauge and i for the computer.
4.0 or 4.7?
ok it only has 1 sensor. have you tried replacing the thermostat?
what degree thermostat did you put in.
what temp reading is the gauge showing at the middle hash mark?
but is there is degree mark at 3 o'clock? like 180 or 210?
ok. well if it aint too much of a pain. put some heat on the sensor and see what the gauge does.
and if you have a digital temp gun, compare the temp where the sensor go into the engine and the gauge or the scan tool
lets do a wiggle test of the wiring to the sensor and see if the gauge jumps...also make sure the sensors connector has a good ground
how about the ground for the connector? it should read no more than 0.2 ohms
in my opinion it has to be the instrument cluster then. you can also try a 195 degree thermostat to bring it to 3 o'clock
directly from the ecm
Here is what the circuit does. The (PCM) provides a 5 volt reference and a ground to the sensor. The PCM monitors voltage drop to determine coolant temperature. If the ECT reads less than freezing temp when engine has been running for more than a few minutes, the PCM determines a circuit fault and sets this code. Or if the PCM determines the sensor resistance is out of specs, this code is set.
dont know the voltage range my friend. and its only supposed to set a code. now if there was a fault with the ect and thermostat operation it would turn on the light
im thinking it means less than what it should read
looks like you're going to half to pull the instrument cluster and do a continuity test between the gauge and the ecm. point to point then to ground