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Fans on all the time....

Big Vern

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Hi folks, just started the old girl up, and the fans are constantly running even though the car isn't warm. It didnt automatically start however when i turned the key just a few moments after the engine started. Not sure where to look,.....Relay maybe?
N/A 1986 S3

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Does your S3 have aircon? That creates another aspect of troubleshooting.

The double-contact fan control relays are a good place to start. On an '86 they should be in the front boot. Don't mix up the single contact type with the doubles.  (On a Stevens car, all dual-contact relays were fitted with a blue plastic socket/base...not sure about G-cars)


If you mess with the relays, make sure you don't leave the bundle where the headlight pod mechanisms can contact them, else you will be starting another topic soon...🥴

Atwell Haines

'88 Esprit

Succasunna, NJ USA

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No, the one on the left appears to be connecting both 87 outputs to 30 at once, whereas the right one is a change over, alternating between 87 and 87a depending if it's on or off. The former is common for headlights etc. 

Nice that they used to have a graphic, replacements might not, and the car has a mix of both so you don't want to confuse them.  Having a spare one of each in the glove box might help with roadside repairs.  Take time to check the relay sockets when you swap them, often the connectors get crusty or overheated.

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Thanks Thomas, i see, im now trying to find a replacement., I can get one from SJ but the Postage is a fair whack. 

Funnily enough i do have a bag of spairs of most things in the glove box, ill add spare relays too!

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Hi Brett,

If you have a multimeter, you could easily test the relay (off the car).

Usually 60 ohms across 85 & 86.

Across 30 & 87a should read 0 ohms.

Across 30 & 87 should be open circuit.

I don't think it will be that relay at fault in this case.


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Unless you're looking for a specific look to the case or mounting tabs, these are very generic items. Both types are available anywhere, very inexpensive,starting at a couple pounds on Ebay, more at your local vendor.


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  • 2 weeks later...

So ive got the correct double contact relay but it makes no difference. i have however found that its only one of the fans that stays on. (Ive not found out if the other one kicks in yet when it gets hot). Ive also check the earths and they also seem fine. Bit stumped now. They are Spal Fans on an Aluminium Rad but they have been running fine for the past couple of years ive had them..... any other suggestions? Im no mechanic but i do have (some!) common sense :)

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Given that they are Spal's someones been in there and its hard to say what the wiring is now, but assuming the wiring's close to original, you might pull the fans fuses to see if that makes the running fan stop. Then you would see if the stray power was coming from the relay side of the fuses or the fan fail side.



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