twincamtim Posted July 12, 2015 Share Posted July 12, 2015 The radiator fan on my 2001 Roadsport 1.8K series has stopped working - it was fine on Thursday but not cutting in at all today. I presume it will either be one or a combination of: fan/switch/wiring/fuse.With my (very) limited electrical knowledge I have checked the fuse and that is intact. Not sure what to do next - any suggestions?PS: I do have a Multimeter - following JK's advice that every 7 owner should have one! - but have never ever used it.Thanks. Link to comment Share on other sites More sharing options...
John Vine Posted July 12, 2015 Share Posted July 12, 2015 If the fuse is OK, the next thing to check is the fan itself. To do this, detach the connector from the sender at the top of the rad, and turn on the ignition. Join the connector terminals with a length of wire. The fan should start (you are in effect bypassing the sender). If it does, the fault lies elsewhere. Try this test first and let us know how you get on.JV Link to comment Share on other sites More sharing options...
twincamtim Posted July 12, 2015 Author Share Posted July 12, 2015 Thanks John, I'll try and give that a whirl tomorrow and let you know the result. Link to comment Share on other sites More sharing options...
John Vine Posted July 12, 2015 Share Posted July 12, 2015 Ok -- good luck!For info, what I described as a "sender" is really a thermostatic switch (not known for their reliability). JV Link to comment Share on other sites More sharing options...
twincamtim Posted July 14, 2015 Author Share Posted July 14, 2015 Hi John,I've just connected the terminals and the fan started so the fault must be elsewhere, as you say. What can I try next please?Thanks. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted July 14, 2015 Member Share Posted July 14, 2015 Clean the connections and make them again. Get the engine up to temperature and if the fan doesn't work as it did when you shorted them the fault lies in the switch.Jonathan Link to comment Share on other sites More sharing options...
twincamtim Posted July 14, 2015 Author Share Posted July 14, 2015 Thanks Jonathan,Are there any tips on cleaning terminals? WD40? Meths? Emery paper? Link to comment Share on other sites More sharing options...
SM25T Posted July 14, 2015 Share Posted July 14, 2015 Bit of emery Link to comment Share on other sites More sharing options...
John Vine Posted July 14, 2015 Share Posted July 14, 2015 If cleaning the contacts doesn't fix it, then, like JK, I'd suspect the thermostatic switch. Relatively cheap and easy to replace -- this one, probably.(Edited to erase spurious comments about 12v supply -- you've clearly got this, or the fan wouldn't have run in your test! Doh!)JV Link to comment Share on other sites More sharing options...
twincamtim Posted July 14, 2015 Author Share Posted July 14, 2015 Hi John.Well, I followed your instructions before you edited them....and at first didn't get any voltage until I realised I hadn't turned the ignition on (Doh! x 2). Once I had done that I got 12.76V, so definitely the switch.I see that the item is currently OOS at CC - any suggestions where I might source one from? Is this something I can swap myself??Many thanks. Link to comment Share on other sites More sharing options...
Mrp Posted July 14, 2015 Share Posted July 14, 2015 before somebody else posts !!!Redline 01883 346515 Link to comment Share on other sites More sharing options...
SM25T Posted July 15, 2015 Share Posted July 15, 2015 Easy to swap yourself .... with cooling system cold. Link to comment Share on other sites More sharing options...
twincamtim Posted July 15, 2015 Author Share Posted July 15, 2015 Just rang Redline and they are putting one in the post to me as I type! Marvellous. Link to comment Share on other sites More sharing options...
nickh7 Posted July 15, 2015 Share Posted July 15, 2015 Its a VW Part 823959481F if Redline dont have one pop to your local motor factors quote that number and they get you one if they dont have it. They are about £12 Regards Link to comment Share on other sites More sharing options...
John Vine Posted July 15, 2015 Share Posted July 15, 2015 Before you fit (delete "order"!) the new switch, check that the rad is full of coolant by loosening the bleed screw. An air gap at the top (where the switch lives) is likely to prevent the switch working properly.JV Link to comment Share on other sites More sharing options...
twincamtim Posted July 16, 2015 Author Share Posted July 16, 2015 Does anyone know the torque setting for the radiator cooling fan switch???Thanks. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted July 16, 2015 Member Share Posted July 16, 2015 Clean surface face and threads, copper grease, wrist tight only. Check for leaks after the first run and a little bit tighter if needed. Jonathan Link to comment Share on other sites More sharing options...
John Vine Posted July 16, 2015 Share Posted July 16, 2015 Don't think I've seen a figure published anywhere. Do it tight enough to begin to compress the fibre washer. If it leaks, tighten a little more. Just don't overdo things if you've got an ali radiator.JV Link to comment Share on other sites More sharing options...
twincamtim Posted July 16, 2015 Author Share Posted July 16, 2015 All sorted.This is the first 'proper job' I've done on the car (i.e. other than checking oil, air and water, etc) and it feels very satisfying - many thanks for all the help! I couldn't have done this without you.... Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted July 16, 2015 Member Share Posted July 16, 2015 Well done.I usually clean connections with a scraper (alright, it's a screwdriver), a wire brush and some degreaser if needed. Then reassemble with a topcoat of WD-40.But I have a suspicion that the major value of the rigmarole lies in finding bad connections between cables and connectors and bad contacts between connectors rather than in removing crud.Jonathan Link to comment Share on other sites More sharing options...
John Vine Posted July 17, 2015 Share Posted July 17, 2015 Well done, and thanks for the feedback. JV Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 19, 2015 Share Posted July 19, 2015 Failure of the fan temperature switch is a common problem and occurs because the switching on and off of the fan causes the contacts to arc. The solution is to add a relay so that the temp switch controls the relay and the relay controls the fan. It's an easy mod to do and, if you have access to your ECU s/w and like a challenge, you can move fan control from the temp switch to the ecu, allowing you to adjust the temperature at which the fan comes on (and goes off). You can also add an override switch. A quick search of the recent archive will find details and a diagram.Paul Link to comment Share on other sites More sharing options...
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