But are you loosing coolant? Or is it just the coolant light coming on?

 

If the latter then it may be same cause as reported on Mk1 Octavia and some other models. The sensor on those models (and probably the same on the Mk2)  is merely two prongs inside the coolant expansion bottle which measures the electrical conductivity of the coolant as a proxy for coolant level.

The fix is to clean contaminants from the prongs by scraping with a screwdriver. 

 

And if its not that, and assuming you aren't losing coolant, check the connection from the earth wire going to the the pin inside the bottle and the car body with a multimeter. I had this light coming on with no leak and it turned out to be that. Ran a fresh wire to the earthing point and its been fine ever since.

just an update guys - I still haven't sorted the issue out yet but I've noticed something...when we had the hot spell a few weeks back I was having to top up with coolant every 2 days now it has cooled down I haven't had to top it up at all!! Coincidence?

14 minutes ago, Pudq1 said:

just an update guys - I still haven't sorted the issue out yet but I've noticed something...when we had the hot spell a few weeks back I was having to top up with coolant every 2 days now it has cooled down I haven't had to top it up at all!! Coincidence?

Quickly, has anyone suggested checking that the fans are working correctly?

4 hours ago, KenONeill said:

Quickly, has anyone suggested checking that the fans are working correctly?

I dont think so no

12 hours ago, Pudq1 said:

I dont think so no

Well, one, I think the LH, should spin any time the AC is on, and both should spin fast when the engine is going onto heat above normal, say 90C.

On 29/08/2018 at 16:20, Pudq1 said:

just an update guys - I still haven't sorted the issue out yet but I've noticed something...when we had the hot spell a few weeks back I was having to top up with coolant every 2 days now it has cooled down I haven't had to top it up at all!! Coincidence?

 

If I had been topping up every 2 days like you (a few weeks back) and there wasn't the slightest sign of it (quite literally pouring out of somewhere) then I wouldn't have used the car at all and I would have it booked in for investigation.

 

The coolant system is (he says jovially) a sealed system and therefore shouldn't require any maintenance in terms of filling up unless there is a leak - now that could be a weap on a cooler/rad or something more serious.

 

It may be possible that the heat had been causing something to swell and allow water to pass and now it's cools this may no be happening but surely you would have seen / smelt it

It seems I am loosing coolant as the last 2 times that it's happened I've looked at the coolant levels and it's very low..

Any plans on finding out why before the first anniversary of the OP?

car has been repaired. It was the coolant housing on the gearbox side of the head