muppetlab 0 Posted January 7, 2010 I know this has been covered before and i have read a few threads and the sticky but cant find an answer. Basically my fans packed up on my VR the other day causing overheating in traffic. Fine i thought must be the rad sender. However some monkey has cut the plug off my wiring and fitted three spade connectors so it can be connected to the sender. I pulled these off and put a meter across and have two positves and an earth. All good i thinks defo the switch. So i test the fans. Bridging the wires i can only get one speed to work when the car was hot not sure if its speed 1 or 2. Now when the car is cold bridging the connections no fan works? Removing the black sender on the thermostat housing and bridging with a paperclip does not invoke the legendary 3rd speed and now i have pulled off the connectors to the rad switch i cant remember which way round the wires go. I think from memory theres a red a red/white and a red/black. Help Please :cry: I Need to know if i can get a plug to reattach so its easy for me in future rather than having to jam three spade connectors in. cheers jez Quote Share this post Link to post Share on other sites
Bruno 4 Posted January 10, 2010 ...my fans packed up on my VR the other day ..... some monkey has cut the plug off my wiring and fitted three spade connectors ...... i can only get one speed to work when the car was hot not sure if its speed 1 or 2. ... now i have pulled off the connectors to the rad switch i cant remember which way round the wires go. I think from memory theres a red a red/white and a red/black... There are three feeds. The large pure red one is the primary 12V feed to the switch. The red/white one is the low speed one; the other is the mid speed one. High speed is turned on via a third sensor fitted to the thermostat housing, which has to have special wiring for it, not normally provided on a non a/c car. The part number to replace your plug to the switch (assuming all the pins are inline) is 893 906 231; if they arent in-line its likely to be 1h0 973 203. Get a vw stealer to source one with the pigtails, solder them onto your existing wires and sleeve it properly with split corrugated sleeving - it gets very hot in that bay! The switch boot is 867 972 525 B. An exposed switch will be compromised within a couple of years. The pinouts are: - PIN 3 = RED - PIN 2= RED/WHITE - PIN 1= RED/BLK or RED/YELL (depends on the year of your car). If you look at the rad switch it does have the pinout numbers embossed on the plastic. If you suspect that your switch is in trouble, I would suggest you get the plug and switch at the same time - so that they match. Now onto the problem. Turn the ignition on whilst you do this or the relays will mess you around. Dont start the car. If you hotwire from red to red/white the slow fan should kick in. If it doesnt then it means that that winding has broken down, then hotwire red to whatever is meant to lead to pin 1 - and the second speed fan kicks in. Now if you arent sure - hot wire to the red-white on the rad fan directly, and to the red-yellow after that, and that will confirm whether the fan or the switch is your problem. Once you've worked it out, your options are: - if the rad fan is the problem - probably simpler to fit one of the spal or other twin replacements with a decent all alloy rad. - if its the switch - then you've had a cheap day. If after getting all this to work with the engine off - it still overheats, then you can only conclude that the brains and controls are not working well. Start by changing all sensors on the thermostat housing. If still no improvement, the fan controller is probably to blame - they werent very strong. Failing that you need to get a vag-com on the car and check the ECU temp readings. I hope thats all clear. Dont even try and rig for permanent speed 1, 2 or 3 cos you will burn out the fan. Its a 350 watt motor designed to run for a max of 1 hour before cooling down. It does not have a thermal cut out so it will burn out. Quote Share this post Link to post Share on other sites
muppetlab 0 Posted January 10, 2010 Excellent info thanks. I have already bridged the plug connections yesterday. have power at all three speeds at the fan connector so have concluded its the fan thats buggered. Going to source a cheap electric fan from the scrappy until i can afford a godspeed alloy rad and twin fans! Thanks for all the help will try and get a plug from the dealers for when i swap the rads over. Cheers jez Quote Share this post Link to post Share on other sites
