Big-ted 0 Posted December 9, 2005 OK, please have sympathy on me with this one... So I've got a new rad fan switch after noticing that the coolant was getting mighty hot and the fan didn't seem to be coming on on my 2l 16v. Now, am I right in thinking that the coolant needs to be drained to fit this? I guess it makes sense, what with the sensor needing to be in contact with the thing it's measuring and all, but until now I'd managed to overlook this. Now, I've changed the coolant on other cars many times before, but I often read horror stories about air-locks and all sorts on here, so I'm somewhat reluctant to do this on my C... So I want to test the fan before doing anything else. Both the fan and the sensor use a 3-pin connector on my car. Is there a way I can test the sensor in situ to verify it's knackeredness, and can anyone tell me which pins to take a 12V supply to test the fan? Many thanks! Quote Share this post Link to post Share on other sites
billinjah 0 Posted December 9, 2005 take the plug off the thermo switch and bridge the terminals, if it comes on whack a new thermo switch in there they are £30 though! Quote Share this post Link to post Share on other sites
Walesy 0 Posted December 9, 2005 Never done it on a valver, but I changed my fan switch without draining the water. I just did it after leaving the car overnight so it was cols and topped up the tiny bit of coolant I lost. Quote Share this post Link to post Share on other sites
Big-ted 0 Posted December 9, 2005 take the plug off the thermo switch and bridge the terminals, if it comes on whack a new thermo switch in there they are £30 though! OK, so switch closed = hot, but which two of the three pins should be bridged? Also, a new thermo switch (for a valver, from GSF) cost me about £12... Quote Share this post Link to post Share on other sites
davidwort 0 Posted December 9, 2005 OK, please have sympathy on me with this one... So I've got a new rad fan switch after noticing that the coolant was getting mighty hot and the fan didn't seem to be coming on on my 2l 16v. Now, am I right in thinking that the coolant needs to be drained to fit this? I guess it makes sense, what with the sensor needing to be in contact with the thing it's measuring and all, but until now I'd managed to overlook this. Now, I've changed the coolant on other cars many times before, but I often read horror stories about air-locks and all sorts on here, so I'm somewhat reluctant to do this on my C... So I want to test the fan before doing anything else. Both the fan and the sensor use a 3-pin connector on my car. Is there a way I can test the sensor in situ to verify it's knackeredness, and can anyone tell me which pins to take a 12V supply to test the fan? Many thanks! If you're quick you won't lose much coolant swapping in the new switch! Air locks aren't too bad on the 16v, but you might need to loosen the top rad hose clamp and wiggle the hose to help get the air out, drive a short way and then top up the header tank if the level drops as the engine cools. You can simply short the fan straight to the battery to make sure the motor is OK. Test the sender by checking the continuity as the water temp rises. Pins shouldn't be hard to figure out from the wiring, again check the loom connector with a multimeter to see which is which. David. Quote Share this post Link to post Share on other sites
Big-ted 0 Posted December 9, 2005 Right. Fan works. It's the two end terminals that need to be bridged for future reference! Guess I'll be attempting the quick swap sunday then, but I think I'll get hold of some G12+, just in case! Many thanks for your speedy help once again gents! ;D Quote Share this post Link to post Share on other sites
saysomestuff 0 Posted December 9, 2005 Right. Fan works. It's the two end terminals that need to be bridged for future reference! lol does it matter which end? Quote Share this post Link to post Share on other sites
Big-ted 0 Posted December 9, 2005 Um, well you have one plug, with three terminals in a line. You connect the two end ones with a bit of wire, and, if your lucky, your tie/knuckles/pony tail get ripped to shreds by the fully functional fan. Oh, wait a minute.... :? Quote Share this post Link to post Share on other sites
bix 0 Posted December 9, 2005 You should be able to get the fan to go fast and slow with a piece of wire, thats why theres 3 terminals! Quote Share this post Link to post Share on other sites
Big-ted 0 Posted December 17, 2005 Update: Changed fan switch today. Fan works spot on. Lost a fair bit of coolant but topped up with G12+ and all is good. One thing concerns me though. The kind folks at GSF insisted I needed an extra brass washer with the switch. Knowing no different, I ordered this too, but when it arrived the switch already had a brass washer on it, although slightly different to the one sent seperately. On inspecting the old temperature switch, it definitely only had the one washer (the one which was on the new switch already) so I'm sort of at a loss as to what I'm supposed to do with this extra washer. Guess I'll just watch closely for any leaks. For now I think it's time to verify correct operation of coling system on my local private road! :D Many thanks for all your help! Quote Share this post Link to post Share on other sites
Supercharged 2 Posted December 17, 2005 Big-ted, you don't need an 'extra' washer... GSF ones come with one already attached, the VW ones use a paper gasket... Quote Share this post Link to post Share on other sites
Big-ted 0 Posted December 18, 2005 Cheers. Exactly as I thought... Quote Share this post Link to post Share on other sites
