Hi,

was picking the father in law up after he dropped his car in for work today, when we got stuck in a bout 30 mins of constant slow moving very heavy traffic. Having never run my VRS in traffic since I've had it, I wasn't sure when the cooling fans cut in.

Ever since I've had it, the temp has sat religiously at 90 degrees, but today after about 15 minutes of traffic it started to gradually creep up. I waited till it got to about 93, expecting the fans to cut in but they did not appear to, so I basically bottled it and turned the climatronic to auto and both fans cut in and down came the temperature.

When I got home, I disconnected the thermofan switch connector and sprayed WD40 inside the connector in case I had a poor connection - all going well so far. Half an hour later I go out to pick up my daughter from work, and after a couple of minutes of driving, on comes the engine check lamp. .

Now I have to buy a code reader tomorrow to see what it is, but a bit of a coincedence that, straight after disturbing the wiring. Are the thermoswitches very dear?, thought I was getting a reliable set of wheels but feeling a bit hacked off at the moment.

Anybody got any particular code reader brand that they think are ok?. Need to sort out someone local to run VCDS on it to see if there are any lurking nasties. If I hadn't only just had the belt and pump changed last month then I might be wondering if it was a waterpump.

Sorry to ramble, bit fed up at the moment.

Thanks in advance for any help

Phil

Dont you have any contact spray? the WD40 is oil based isnt it so might not be connecting right? the contact stuff from Toolstation is good, I used it on my drivers door and so long as you wipe it and leave to evaporate its brill.

might be worth a go.

might have a dodgy thermostat?

best thing is th VCDS to see what it show. will prob be someone near. iirc the was or still is a part in the VCDS section that shows where the VCDS owners are?

Hope you sort it mate, they are good cars really

could be a number of things but yes the themo switch can play up so you get both fans wth aircon but no fan on normal running.

The fans are controlled by various relays that sit under the battery(Fan control unit) That can play up ( i had a poor connection there and car overheated) Also the top battery fuse box has fan fuse (middle green fuse) that can have a poor connection and possibly a blown fuse or faulty fuse. Failing that the fans could be playing up as well. My overheating caused water pump to break and that was a costly cambelt /waterpump change job so don't let the car overheat if you can help it.

Drop a PM to Delcac, I think he's the nearest person to NW Kent I know with VCDS (he's in Chatham).

Did you have a chance to check if the pipes felt really hot or coolant was starting to boil? When my coolant temp sensor went the temp gauge went into the red which had me panicking but the coolant was still normal it just needed a new CTS. If either the CTS or fan thermoswitch is goosed that'd bring up the engine light.

If the thermostats broken it usually runs noticeably cooler than normal (less than 90 if you're driving around) as the thermostat fails open rather than closed

Hi all,

thanks for all the kind help, really sorry for my bad attitude yesterday - just really frustrated.

@Bowders1 - I've checked the fuse in the battery box and physically removed it and it looks ok, do I have to remove the 2 x 10mm bolt forward of the battery to drop off the fan unit to check it or is it a plain get down and struggle job?. I have checked both fans and they are free to turn and both rotate with the aircon on auto with neither noticeably slower than the other, so I take it they are ok?.

@chicken_eyebrow - The CTS is a green one and does not look very old, but I know that means nothing if it's fubar, but do the new ones fail regularly?. This is the wierd thing, coolant level wasn't massively raised like a car ready to boil, and the rads were near normal temp to the touch, it was just the gauge steadily rising a degree every minute or so. Like I said above, I bottled it and turned the aircon to auto - I normally run it in econ mode and this sorted it, but no engine light came on at that time, it was only after we disturbed the thermo fan connector and I'd driven the car a couple of minutes that the light came on.

I am going to get the car scanned first to make sure I'm not chasing a coincidence and that some other sensor in the car has failed at the same time. Wierd thing is the car drives like normal - no LIMP mode or anything. Provided I take care, is it ok to use the car with the engine light on or is this not on?, I have no backup red warning lamps coming on at all just the yellow engine lamp.

Once again a big thankyou to you guys for trying to help me out.

Phil

If the main rad fan isn't coming on in traffic then there's definately something up with the thermo switch, it should come on as soon as the coolant starts heading towards 100 degrees to bring it back down under 90 again.

Your fault code scan should tell you whether its a fault with the CTS or the fan switch. Mine went right into the red straight away rather than climbing but when I saw the coolant wasn't boiling and the hoses didn't feel red hot I drove it to my local garage who diagnosed it as a faulty CTS (I'd fitted a cheap one off the internet).

I would just be really really sure before driving it that it's not genuinely overheating, and if the rad fan isn't working then either turn the aircon on to force it to work or avoid driving in traffic until you can get it sorted. As Mark said they don't take kindly to being overheated, you could damage the waterpump or worst case head/headgasket.

Update,

Went to Skoda dealer this afternoon - needed to get to bottom of this as was just agravating not knowing. The guy used a handheld scanner and found codes 17524 and17705. He said the 17705 was probably down to the breather hose being split and that it hadn't done enough duty cycles to forget it since I changed it. The switches check out ok, but I think I will change the rad one to be on the safe side. The 17524 code remains, but it is not switching the light on, - further investigation there - he was wondering if the other breather hose has perished too. I will check these, rectify what I have to then get another scan.

I can only say a big thanks for all the help so far - it really is very much appreciated.

Have a good weekend

Phil

17524 is a lambda sensor playing up. Not sure that either of those codes would affect the cooling but maybe changing the fan switch will get the fan working again and that will be that.

Have a good weekend too

Yes, would tend to agree, but can only think that presumably the switch has some kind of wax element in it, so that may have failed, but electrically it is still good - soon find out when new switch is in.