overheat light , car is cold ?

gaRy cupra

Guest
a few times during the cold period recently whren turning on the ignition or just a few minutes after starting the overheat light at the top of the temp gauge has been flashing but the car is cold because its beeen sat all night if you switch off ignition and turn it back on the light stays off ? anyone any ideas ?
 

Cupra Ross

Breaks things............
May 15, 2005
1,380
1
Edinburgh, Scotland
a few times during the cold period recently whren turning on the ignition or just a few minutes after starting the overheat light at the top of the temp gauge has been flashing but the car is cold because its beeen sat all night if you switch off ignition and turn it back on the light stays off ? anyone any ideas ?

Yes, you need a new coolant header tank (the thing you see the coolant level in). The sensor in it is prone to failing and its telling you that there's no coolant in the car even when there is. Try scraping the two metal prongs in it with a screwdriver, this cleans the residue from it and sometimes stops the problem.
 

ian_cupra

Guest
check coolant level, if thats ok could be that the sensor in the coolant tank is goosed
 

DAN T

Guest
the same problem to , i will try the trick with the screwdriver. why just when is cold i thought is the temp sensor . i hope the will work
cheers
 

andycupra

status subject to change
ok, so can we confirm that you get a bleep? i think it bleeps 3 times for low coolant levels..!?

why when cold? well the coolant level will be lower the colder it is and possibly the electrical connector plugs get affected by the cold? ive had two leons, both have suffered from it even when the coolant was within the correct range. - both however worked fine when i ensured the coolant level was at the top end of the correct range. (when cold!) when the coolant is hot it will be above the top line due to expansion.
So i would ask is it at the top end of the correct range?


The next thing would be to take the expansion tank lid off, then wiggle and scrape the two metal prongs you can see in there from the sensor.
Then remove the sensor electrical connector plug, ensure all contacts are clean and give a good contact and then plug back in. (if you have any electrical conduction gel or something that may improve the contact then that would be good).

see how it goes,
if this doesnt help then you can buy a new expansion tank.
(although im not aware of any change to the design and so in a year or two it may do the same).
 
Last edited:

mini

Guest
over heat light

hi there iv had the exact same problem, but belive it or not it was because i parked on my drive,which is quit steep!!! so the car was getting a COOLENT TOO LO message wen really it was fine. i tried it owt over the last week by parking on a flat,lo an behold- no problems, no warning light or beeps