Red light on temp gauge

[Gudgie]

Hi all, I've been having an intermittent fault with the red warning light on the temperature gauge coming on with the same beep as when the fuel light comes on!
It seems to happen on cold starts and if the engine is turned off and back on again then the problem disappears! Its not throwing up any codes and no EM light etc!
Does anybody have any ideas as to what could be causing this!?!?!?
Many thanks in advance

 

[Gudgie]

Forgot to say that its and LC180 52 plate with AUQ engine

 

[dave_ph]

that will be the sensor in your coolant tank.

Take it out, give it a clean, pop it back in - jobs a good'un

Happened on my old 51reg 1.6 leon in the winter as well

 

[Gudgie]

Nice one! how do i clean it though? do i just scrape any crap off the prongs or will this damage the sensor?

 

[dave_ph]

i think you can just scrape can crap of the prongs iirc

 

[mark1231]

get new tank.the sensor will not come out cost about 15 quid

 

[andycupra]

very common.
as dave has said, its the coolant level sensor playing up.

You will see two metal prongs protruding into the coolant if you remove the coolant expansion tank lid.
Give these a wiggle (gently). Some say scrape these with a screw driver, but ive never seen any crap on the prongs!

Also if the coolant is at the lower end of the normal range when cold, top it up a bit. (the level will be higher when cold, which is ok). Level should be correct when cold.

The reason we get loads of thread like this in the winter is as its colder the coolant is at a lower level, (water expands the warmer it is)
Combined with the sensor not being so efficient at low temps this is why i suggest topping up the level so its within normal range, but towards the top end.

If you wanted to be thorough you could unplug the sensor and clean the contacts.

 

[Gudgie]

Cheers Andycupra. You pretty much answered my next question before i had even asked it! I'll give it a try when i get home tonight

 

[ENTERNAMEHERE]

Ta-da! Great search function. This is what has just started happening to my 2005 LCR. Thanks folks!

 

[andycupra]

let us know how you get on

 

[ENTERNAMEHERE]

let us know how you get on

Warning light issue has stopped, today its slightly warmer outside. Ordered new expansion tank with sensor. Thanks folks

 

[mattcymru]

my leon has suddenly started doing this, ive noticed the coolant is slightly low too....what coolant do i need and is it a case of just pouring it in neat? is there a max mark too?

thanks!

 

[andycupra]

yes there is a min and max mark. - for when coolant is cold. The level will be higher when hot.

YOu want to use the same stuff again, (never mix different colours)
The pink stuff is G12 and available from all VAG group dealers. not Pricey and usuallyin half or litres bottles.. it needs to be diluted 50%.

 

[mattcymru]

hmm the current coolant looks orange, i can see a min mark but no max! how much higher than the min mark is it, roughly?

cheers!

 

[mattcymru]

sorted now! for info needed a new temp sensor!