Hi Guys, and ladies.

With the cold weather we have just had my octavia ellegance 110 tdi has developed a fault with the coolant level sensor and or the coolant temp sensor. Unfortunately I dont have access to a vag com and I wondered if anyone out there knows if I can test these with a DVM and what sort of reading to expect. The only alternate is to go to a dealer, but will vag com indicate which sensor is faulty. Many thanks and a happy new year to everyone.

Hi Guys, and ladies.

With the cold weather we have just had my octavia ellegance 110 tdi has developed a fault with the coolant level sensor and or the coolant temp sensor. Unfortunately I dont have access to a vag com and I wondered if anyone out there knows if I can test these with a DVM and what sort of reading to expect. The only alternate is to go to a dealer, but will vag com indicate which sensor is faulty. Many thanks and a happy new year to everyone.

whats the fault thats happening? its might be a common fault we can help you with

whats the fault thats happening? its might be a common fault we can help you with

Many thanks for the reply. After starting engine the temperature coolant light comes on and gives three beeps. The book says to check coolant level and fan fuse. Everything appears to be ok. If I run the car, again everything seems ok except the light stays on, this is the red image of a thermometer. The temperature gauge goes to its normal position. ( About 90) . All this leads me to believe that either the coolant level or coolant temp sensors are faulty.

The coolant level check is an easy one to cure. Sure I posted on here about a week ago for someone else with the same problem. The sensors in the coolant bottle are just a couple of long metal prongs which stick into the coolant solution.

Over time these prongs build up a collection of bubbles, thus reducing their surface area for electrical conductivity. This fools the car into thinking there is less fluid in the expansion tank than there really is. The quick and easy solution to to resolve the issue is to take the cap off the bottle and use something like a long flat-head screwdriver to "scrap" the bubbles off the prongs. I guess a wire coat hanger could be used too. Don't forget to put the cap back on the tank once you have finished.

I have had to this once in the 5 years I have owned my car. The other more expensive solution is to replace the expansion tank (which a previous owner to me had done, according to the invoices but that might have been for a separate issue).

If the above does not help then you might need to get the car hooked up to vag-com. iirc the previous person who posted said they had a red temp gauage light. I had a feeling mine was orange, but it was a long time ago when I last saw it!

It's a common one

The prongs in the exspansion bottle are furred up, either scrape them with a screwdriver or replace the bottle.

HTH

It's a common one

The prongs in the exspansion bottle are furred up, either scrape them with a screwdriver or replace the bottle.

HTH

Thanks a lot to all you experts out there, that has saved me a bundle no doubt. Just been out to the car with a thin piece of wood dowling with a small bit of nylon scourer attached and given the prongs a good clean. NO LIGHT ON NOW. Very many thanks.

Thanks a lot to all you experts out there, that has saved me a bundle no doubt. Just been out to the car with a thin piece of wood dowling with a small bit of nylon scourer attached and given the prongs a good clean. NO LIGHT ON NOW. Very many thanks.

Excellent, glad to hear it is fixed :-) Sure if you had taken it to a dealer they would have just replaced the bottle!

there only £11.21 anyway so not massively expensive