Replacing the coolant sensor on FIAT 500 : key answers you don't find anywhere else.

Here Im answering a few questions:
Where is the coolant sensor located.
Can you replace the sensor without draining the coolant?
How to disconnect the actual sensor plug.

[@vettle1]

Drain and replace for air? Just bleed \burp system.

[@edgardopabon8100]

Question? My 2013 fiat 500 had today the diagnostic 0099972 coolant temp sensor, because the ac cooling fan is not working,after already checked the high speed and low speed relays, fan motor, valve pressure transducer etc, this sensor was the next diagnostic You think that could be a problem or relation with? and where can i get this sensor cheaper, again thank you for your video very good explanation 👍🏽

[@mauro_mirez]

Thats a curious problem. So, let me first confirm it: you turn the AC on and no air is flowing? Regarding the coolant sensor one test you may do is disconnecting the sensor cable, turn the engine on (I will expect false coolant sensor errors showing up in the dash at this point) and test the AC again to see if is there any difference. Now, regarding replacing the sensor, there is something you need to know. First of you can find it in ebay. Im not sure if you can get the sensor only. It usually comes attached to the pipes receptor you can see here at 0:53 The thing is you if this pipes receptor has never been replaced, the original contains plastic pipes receptor that, keeping the year of your car, are close to break down at the moment you try to replace the sensor. So, be careful with them of be prepared to fully replace that as well ( the new one is fully metallic) So far, I do not think this sensor is related to your problem.

[@haseebshah3707]

Hi my fiat 500, the fan comes on as soon as the car is started. The fuse box has been messed around with so can it be a wire or do you think it’s a sensor. Relays are ok. I was thinking maybe the sensor is faulty so sends faulty signals and then fan comes on when car is on. Even when cold start, it’ll be on full speed. So something is definitely wrong.

[@mauro_mirez]

Hey Hi! Yeah it definitely points to be this sensor Im talking about in clip. When it fails, the fan gets permanently activated as a way to assist the motor to cool down because the ECU just has no way to tell if the engine is hot or not due to the faulty sensor. Now, be prepared to also have to replace the part that receives this sensor. It its never been replaced before, the pipes tend to dissolve on your hands as they were wrongly made of plastic instead of metal. The new spare is full metal so its worth replacing to avoid being broke down in the middle of the road later on.

[@Dr...D]

thx mauricio

[@mauro_mirez]

Sure, any time.

[@sandeepgc9668]

Hi there,my coolant guage is not working and i see blue or black smoke coming out when i start the engine,but not everytime the smoke comes out,its random..and it stops in few seconds.Do you think the sensor is out or other stuffs...what shall i do??

[@mauro_mirez]

Hi! Scanning the ECU and see error codes on startup is a good start. Have you noticed any difference between any random startup and the first time you start the engine in the morning? Now, when I researched about the coolant sensor issues I found cranking problems and white smoke on startup as potential symptoms. So, replacing it is definitely something you need to do. So, you can just replace it and then see how it behaves afterwards.

[@conniesilva2581]

Is this the same location for all fiats? I have a 2016 fiat 500X

[@mauro_mirez]

1st off, yours is a 500X. That X is quite something. Your car is way bigger so I can't guarantee anything. Where are you? Maybe that can help narrowing down the answer.