Thermostat valve / Radiator Fan issue: URGENT

I own a Fiat Linea diesel Emotion 2009. Radiator fan does not start even at mid temperature mark of gauge without AC. However, with AC on, radiator fan works.

To my surprise, temperature needle stays at half mark even when coolant starts to boil and radiator fan doesn’t kick in without AC.

To test, I accelerated roughly in city without AC to check the radiator fan kick in with rise in temperature which in no time rose to half mark but fan doesn’t kick in.

I replaced the coolant temperature sensor with new one (Old one was also fine) and still fan doesn’t start without AC.
Mechanic had put a candle light heat on the sensor when attached to a circuit, and the fan started without AC on.

He’s of the opinion that the hot coolant might not be reaching the sensor due to bad thermostat valve and suggested full thermostat elbow replacement which included valve, temperature sensor and other minor components.

Should i go for it ? Need guidance.

 

No expert here. Did you took the second opinion of any FASS or some other FNG?
@Inderpreet Bajwa

 

I got the car scanned at Jeep-Fiat auth. Service centre and the error code came was coolant temp. Sensor so i got it replaced with new one as I mentioned before but still radiator fan doesn’t turn on at mid mark of gauge...in fact, never without AC.
Problem of coolant boiling comes mostly in City Traffic with or without AC and while going up hill.

Mechanic was of the opinion that it could be issue in module or anything else so he asked to leave the car for 2 days which I didn’t because i heard many stories of corrupt service centres that’s why i rely more on my local mechanic.

So, probably it seems an issue of thermostat valve not opening.

• Also, can somebody pls confirm whether Linea and Tata Manza/Vista or Maruti S-Cross/Ertiga share same thermostat elbow ?
I saw the pics and found it to be identical.
It’ll be easier for me to get the part if found identical.

Abhishek sir, if u could tag or notify TFI members whom u know could provide additional information or guidance on the above mentioned issue, I’ll be really thankful to u.

 

Not much people visit teamfiat nowadays. @asimpleson, if you can point out something here to help @Inderpreet Bajwa .