Faulty Coolant Temperature Sensor?

[Brettannica]

Hi All,

Yesterday my car started to beep three times just after a cold start up with the red Coolant light flashing continuously and the radiator fans kicking in and continuously running, shutting down when the vehicle is turned off.
The dash check button states that I am to shut the car down and check the coolant fluid level.
Fluid levels are correct, with no drop or telltale residue to indicate a leak.
Temperature gauge builds to temp in the usual timeframe and sits at the 12 o’clock (90ºC) and does not drop or waiver.

I’ve read through what previous posts I can with this almost being an exact replication;
http://www.audizine.com/forum/showth...at-or-Rad-Hose

I’ve disconnected and reconnected the fluid reservoir sensor to check for any dirt of loose fitting - all appears fine.

As stated in the link above, I’m also starting think the Coolant Temperature Sensor located centrally below the PCV valve has gone bad???

Here’s where I’m confused. ECS has what appears to be three kinds listed. 2 are listed as being located in the cooling flanges (no idea where these hide) and one listed as Coolant Temperature Sensor With O-Ring & Clip - 4 Pin - I’m thinking is this the one but would like some confirmation.
Has anyone else experienced this issue?
How annoying is the fix?

In the mean time, I’ve pulled fuse #4 to shut the fans down.

Thanks in advance for your help. I’m in Australia and parts are either f***ing expensive or non-existent, hence checking before I purchase in the US and ship it down my way.

Edit: Just took it for a drive with a few short bursts. Temp gauge stayed steady. Just the annoying red coolant light continuously flashing.
There is however the sound of a small motor?/fan?? running for approx. 5 minutes post shutdown which I can’t pinpoint, but I can feel the vibration through the hose running to the expansion tank. The coolant level has also about 10mm in the expansion tank.
A Toyota Yaris is starting to look appealing.

[Wiggler]

Yesterday my car started to beep three times just after a cold start up with the red Coolant light flashing continuously and the radiator fans kicking in and continuously running, shutting down when the vehicle is turned off.

If it is taking a little while for the coolant warning to come on could the the thermostat is stuck (partially) open, so engine takes a little longer to warm up and throws a fault because of that. Happened to me, and I think I had some fan weirdness too that also went away after replacing the thermostat.

If you don't have the Ross-Tech software/cable it's worth it, fault code will help you figure out what is going with this and other things ...

[VinnysS4]

i was going to say....just plug it into a ross-tech and check the coolant temp sensor...might save you a ton of time and money

[Brettannica]

Thanks Wiggler and VinnysS4

I had it scanned today and it appears to be the sensor.

[VinnysS4]

im glad that you got it sorted out. I hate having little things go out and not knowing where to look! I bought a Ross-Tech cable just so i wouldn't have to pay someone else to scan my car. Plus i've already done a few things to my s4 that i love!