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Searched the searched but couldn't find what I was looking for. Anybody know the location of the engine coolant temp sensor? My coolant levels are all full /good, but my fan is constantly staying on and my DIC says, Coolant ------*F

Thanks, Jeff
 

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Searched the searched but couldn't find what I was looking for. Anybody know the location of the engine coolant temp sensor? My coolant levels are all full /good, but my fan is constantly staying on and my DIC says, Coolant ------*F

Thanks, Jeff
From the manual it looks like it is on the rear passenger side of the engine in between the heater hose inlet and outlet on the thermostat Housing. It appears to be in the same place on both the LE5 and LNF Engine.

I didn't know it was all the way back there. I'll have to go check it out.:yesnod:

Sure enough just south of the exhaust manifold. Looks like it might be a knuckle buster to change the thermostat.
 

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Sounds like an air bubble....numerous threads on it in advanced search....Skip....:):D:)
 

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This may be your thermostat. Holler at JR or Hal. :yesnod:
 

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I just had my thermostat replaced and now the fan seems to stay on an excessive amount of time after I turn the car off. I was told it was normal...:rolleyes:
 

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Doesn't seem like a bad thermostat or an air bubble is going to give you a blank temperature display. I'd check the wiring at the sensor first before I started draining fluids. May just be a loose or broken connection.
 

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Try to find someone with a scanner that will show sensor data. The way you diagnose a failed sensor is to read the sensor data with the engine cold. You compare the intake air temp sensor and the coolant temp sensor. They should be within five degrees of one another. If you don't have the sensor resistance curve for temperature, it's more difficult to say how precisely the sensor is performing as temp rises. You can only see if resistance changes (it will fall) as the coolant temp climbs. You can do this with a simple multimeter.

I don't have a service manual for a Sky but if someone here who does, see if there is a separate sensor for the computer input and one for the gauge. It is this way in some cars. I'd be surprised a failed coolant temp sensor wouldn't set a code since the algorithm to set this code uses time, distance, and sensor reponse to trigger a code. Also, the sensor would still show a reading even if there was no coolant at all since it's a simple thermistor and the hotter it gets, the lower the resistance. It would change it's value slower since air is a poor conductor, but it would still change.
 

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Try to find someone with a scanner that will show sensor data. The way you diagnose a failed sensor is to read the sensor data with the engine cold. You compare the intake air temp sensor and the coolant temp sensor. They should be within five degrees of one another. If you don't have the sensor resistance curve for temperature, it's more difficult to say how precisely the sensor is performing as temp rises. You can only see if resistance changes (it will fall) as the coolant temp climbs. You can do this with a simple multimeter.

I don't have a service manual for a Sky but if someone here who does, see if there is a separate sensor for the computer input and one for the gauge. It is this way in some cars. I'd be surprised a failed coolant temp sensor wouldn't set a code since the algorithm to set this code uses time, distance, and sensor reponse to trigger a code. Also, the sensor would still show a reading even if there was no coolant at all since it's a simple thermistor and the hotter it gets, the lower the resistance. It would change it's value slower since air is a poor conductor, but it would still change.
@77 deg F according to the manual the sensor would have 2,796 ohms resistance @ 68 deg F it would have 3,520 ohms resistance. 9 degrees change would be 724 ohms which would be about 80.4 ohms per degree F.
although thr RTD probably isn't perfectly linear and there will be a small difference between any given sensor. that should get you in the ballpark

When a temperature display to reads ---F You generally have either an open RTD or an open wiring circuit . Essentially the display is an ohmmeter calibrated to display it's readings in deg F or deg C according to the resistance characteristics of the RTD it is calibrated to.
Therefore ---F would essentially be infinite resistance. So check your connections and wiring.
I am surprised you are not throwing a code. But I don't see a code in the manual for an erronious water temperature reading.You would think it would at least tell you the car is overheating.
I am not surprised that your fans run all of the time though because the temperature reading is so high that it would cause the controller to switch on all of the cooling fans. or in the case of the LNF run the fan at high speed.

There is only one coolant temperature sensor in the vehicle.
Yes, A dashhawk or similar device that can read live sensor data and error codes would be handy if you know someone that has one..
 

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so did you ever figure out the problem because my sky is doing the same thing with the _ _ _ f was it the temp sensor or the terostat
 

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From the manual it looks like it is on the rear passenger side of the engine in between the heater hose inlet and outlet on the thermostat Housing. It appears to be in the same place on both the LE5 and LNF Engine.

I didn't know it was all the way back there. I'll have to go check it out.:yesnod:
Doing my due diligence here. This is correct!

When looking for the sensor from the passenger side of the car, it is right of the thermostat housing, and left of the exhaust manifold.

You will need to take off the windshield cowl to access the sensor, but its not a big deal. A flathead screwdriver for the plastic rivets, a 7mm socket for the screws, and a 15mm socket for the wiper arm nuts.

Take the negative side off the battery.

I removed the pigtail from the sensor attached to the engine block and cleaned both using CRC MAF sensor cleaner. Cleaning both the pigtail side and the coolant temperature sensor side on the block helps clean any debris that gets in there, and trust me, it does!

After letting both sides dry for about 15 minutes, just reconnect, put the negative back on the battery and start the car. Let the engine get up to normal operating temperatures "factory thermostat is 200°F", to verify that cleaning it fixed the issue.

Finally, turn off the engine and put the windshield cowl and wiper arms back on the car.
 

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Update to this problem. I was driving my SKY and the "check engine " light came on. When I checked the DIC displays, the Temperature screen showed ---*F. I read this forum and got under the hood to check the sensor. I jiggled the wires, sensor, etc. but same result. Made an appointment with garage to check the code.
On the way to the garage, the temp screen came back to normal and displayed the coolant temperature. I had the garage read the code, it was P0128.
I had them clear the code and everything has been fine So, as stated above, clean the sensor and check the wires. This may clear up the fault.
 

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Update to this problem. I was driving my SKY and the "check engine " light came on. When I checked the DIC displays, the Temperature screen showed ---*F. I read this forum and got under the hood to check the sensor. I jiggled the wires, sensor, etc. but same result. Made an appointment with garage to check the code.
On the way to the garage, the temp screen came back to normal and displayed the coolant temperature. I had the garage read the code, it was P0128.
I had them clear the code and everything has been fine So, as stated above, clean the sensor and check the wires. This may clear up the fault.
P0128 could be the sensor or it could be the thermostat. Since you were seeing the ---*F I'm guessing it is a sensor issue since the sensor will read down to ambient. You may have a sensor going bad or a plug going bad and something just happened to put it right while you were driving. Keep an eye on it and if it happens again, I'd suggest replacing the sensor.
 
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