Over temp warning light flashing when engine is cold

Mitchy

TTRS
Oct 12, 2004
2,310
0
Oh well atlest when a search is carried out from now on a prop thread description name will come up. lol

If you had searched coolant gauge, or early morning beeps or coolant flashing light about 1 trillion threads about the subject would have come up.

I wouldn't search ''over temp warning light flashing when engine is cold'' for sure;)

If its red flashing it means your level is low.
If its amber flashing it means your prongs need descaling or a replacement expansion tank is needed.
 

Craig j

Guest
Well it isnt low on coolant and the red light was flashing? i cleaned the prongs and as a few other people suggested it cleared the fault.;)
 

roberts189

Guest
Yep mine has started doin this, this morning so later il try the scraping thing and topping up my coolent, it was realy cold this morning like -4.5 and it has neva done it before. Mine stayed on all the way to work tho even when the car had reached temperiture, does everyones do this??
 

Jonesy

Leftie and Proud
Sep 27, 2004
420
0
Pig Hill
what a coincidence ;)

seems mine felt left out and decided to do this twice as well, in the morning yesterday and today...

Turned off and on problem solved, so I too wil be cleaning my prongs later :D

Oh and and I justed searched for 'temperature' ;)
 

andycupra

status subject to change
mine was doing it everyday, then i scrapped the prongs, had not done it since and not even today.

However, after some discussions on another thread, we thought it may be the contacts on the sensor, so if anyone feels helpful can they try taking the sensor plug off and on and giving it a wiggle to see if this helps.
Or...
wiggle but dont scrape the prongs...

thanks! :)
 

Teasy

Active Member
Sep 1, 2007
451
1
Middlesbrough
Mine was ok sunday morning but back to red light & 3 beeps today - I'll be back to steelers AGAIN.......ASAP!!!!!!!!!!!!!!!!!

[:@]
 

Teasy

Active Member
Sep 1, 2007
451
1
Middlesbrough
Took it bask to steelers today, apparently the sensor is situated high in the washer fluid tank so they topped it up over the sensor.
I asked if this would be a problem when the engine reached 90 degrees - he said no, I hope he's right!!! :headhurt:
 

andycupra

status subject to change
Took it bask to steelers today, apparently the sensor is situated high in the washer fluid tank so they topped it up over the sensor.
I asked if this would be a problem when the engine reached 90 degrees - he said no, I hope he's right!!! :headhurt:

washer fluid? or coolant?
washer fluid is for spraying on the windscreen...
coolant is what stops your engine cooking itself...

im not a qualified seat mechanic, but the coolant system is basically a sealed system and coolant expands when its hot. Therefore the space in the expansion tank allows for this. (air can compress, water cant).
So having the expansion tank totally full is not a good idea as it cant do what its there to do, ie allow the coolant to expand. If the pressure gets too high it could blow of a pipe etc etc.
Depends how full it is if its a problem or not.
 

Teasy

Active Member
Sep 1, 2007
451
1
Middlesbrough
Sorry, I should have said coolant resoviour tank - NOT screen washer tank.

They should know what they've done is ok but it's not totally full (car will go back if damage occurs as it's still under warranty and this work got done on the warranty)
 

jidarmy

Guest
guys, i need further help with this problem - in short my water pump bust so i got the warning and overheating engine. I have replaced the pump and the collant system is working fine however when i start the engine (even if its stone cold) or indeed simply when i turn on the electrics and not the igniton at all, i get the 3 beeps and warning light, it does it every time i drive!

i have replaced the header tank as was an easy 2 min job and have replaced the coolant temp sensopr and still no joy, any ideas?
 

Hirdmeister

Guest
mine was doing it everyday, then i scrapped the prongs, had not done it since and not even today.

However, after some discussions on another thread, we thought it may be the contacts on the sensor, so if anyone feels helpful can they try taking the sensor plug off and on and giving it a wiggle to see if this helps.
Or...
wiggle but dont scrape the prongs...

thanks! :)

been watching this thread as mine has the same problem... can someone point me to where these prongs are that need scraping? i'm crap with mechanical stuff!
 

andycupra

status subject to change
been watching this thread as mine has the same problem... can someone point me to where these prongs are that need scraping? i'm crap with mechanical stuff!


find the coolant expansion tank.
Clue: its whiteish, sort of round, filled with coolant and near to the offside suspension turret. (oh and under the bonnet). ;)

If you remove the lid, (do this when the engine is cold as coolant get hot and steamy).

Look down into the coolant tank and you will see two straight metal prongs. Give them a scrape and a wiggle, - but not aggressively so.
It may also be a good idea to remove the wire connector on the outside of the expansion tank, give the contacts a clean and replace.

Also note that this is a coolant level warning, and as coolant levels are lower the colder it gets, it may well just be doing its job. So what is the coolant level like? if its within the ok level but as the bottom edge you could top it up a bit which usually helps also.
 
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andycupra

status subject to change
guys, i need further help with this problem - in short my water pump bust so i got the warning and overheating engine. I have replaced the pump and the collant system is working fine however when i start the engine (even if its stone cold) or indeed simply when i turn on the electrics and not the igniton at all, i get the 3 beeps and warning light, it does it every time i drive!

i have replaced the header tank as was an easy 2 min job and have replaced the coolant temp sensopr and still no joy, any ideas?


this warning is a coolant level warning, which tend to come on when cold or in the winter months. The sensor has two prongs that go into the coolant, and i guess it works on conductivity. So when the coolant level is low, or temperatures are low and electrics dont work as effectively you may get issues with this.
just wait another month and there will be loads of thread on this issue.

Fixes inclue:
replacement of header tank and sensor. - which you have done.
cleaning / scrapping of the prongs.
Checking / imcreasing level of coolant.
Making sure the sensor contacts are clean and good.

If i was you id take a look at the coolant level when its cold. I suspect the coolant level while ok may be lower than it was previously. So if its ok but at the lower end of the ok range, top it up a bit. This helps in most cases.

If the coolant level is towards the top of the ok level but you still get the issue, given this has happened on two header tanks it could be the sensor contacts in the sensor plug / wiring. - however i assume if you turn off the ignition after a short drive and then on again it does give the warning? if so im sure topping up the coolant a bit will help.
 

Hirdmeister

Guest
would that be behind the water bottle for the washer jets?

I've just read this and havent had a chance to pop the hood yet.
 

Hirdmeister

Guest
ok, popped the hood and unscrewed the top and seen the 2 prongs that go into the coolant liquid...

the level of the liquid is roughly at the base of the LOW letters, so just above the line.

I will try and top the liquid up first and see what effect it has - i have a Leon FR 1.9 FR 150 TDI... can i get the coolant liquid from Halfrauds or is at a buy from the dealer direct?
 
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