Dual Fan Wiring

[215m3]

Hi

On preparing my car to get on the road this summer I am going over a few parts. The dual fan relay needs replacing and am looking for some help. There are a few questions below: -

1. In the picture below there is a cut wire(arrowed), does anyone know if this is meant to be cut?

2. Also how many wires go to the relay?

3. It also looks like the wiring to the fan bypasses the relay too?

4. What is the upgrade for this relay part that has been mentioned?

5. Can someone who has a correctly fitted fan and wiring to the relay post a picture of their setup please?





Thanks in advance

[Colin]

Hi Toby
I have uploaded a couple of photos which are images of my car before restoration and one after where the fans work perfectly well in both cases. I have fitted a new loom so the colours may be more visible.
There is also a Powerpoint presentation in the Technical Information & Documentation of the forum.
Right down towards the bottom under the S3 Parts catalogue its shown as S3 Fan wiring diagram (animated) this should help you.

Try and drop this link into your internet address for the presentation.
https://www.dropbox.com/s/niqvpd3w5tcfe ... ppsm?dl=1l

You can pan in on my photos which may help. This is a UK car No AirCon





Good Luck
Colin
S3 V12 2+2 under full restoration

[215m3]

Hi Colin

Thanks for the pictures, all I can say is oh dear. Will need to see if I can work out why your relay has 5 wires going to it and mine has 2. Will need to chase them back when the radiator is off.

[PeterCrespin]

Will need to see if I can work out why your relay has 5 wires going to it and mine has 2. Will need to chase them back when the radiator is off.

I suspect the only thing you actually need to work out Toby, is where to buy your workshop manual if your dad didn't get one during his ownership. As it happens, there is a wiring diagram in the little blue handbook you do have. This will reveal all, plus save you time and backache.

HOWEVER, Series 3 cars do not have overheating problems, so if yours does do you think it might be connected to butchered cooling fan wiring? Might it be an idea to sort that out with a ten quid manual and see how she drives, before splashing out ('scuse pun) on five hundred quid's worth of possibly un-needed cooling system parts?

[215m3]

Thanks for your reply Peter.

Looks like I need to get a quick course in reading wiring diagrams!

When my dad got the car back from Flying Cat on it’s journey home the oil pressure dropped. They picked it up and was instructed to deliver it in person when fixed. They parked the car on the drive, no issues, Dad turned the car round and the car promptly spit all it’s coolant out. It has not been moved since.

The radiator and header have seen better days and will probably benefit from a new core. My plan is now to also review the wiring and see if I can compare it to the manual.

[Colin]

Hi Toby
I found the Coventry Auto components S3 wiring diagram much easier to follow than the workshop manual

They are available on eBay for £10.50.
I have dropped in the link below

https://www.ebay.co.uk/itm/Classic-Jagu ... ect=mobile

You may be better biting the bullet and renewing the electric fan looms which plug in to the main loom which are available from Autosparks or Barratts or Robey it depends if your an expert or a novice like me, that route may make life easier.

The relay or the Otter switch could be suspect as well so you may well have to replace those as well

Good luck
Colin

[Ole-xke1974]

Hi Toby,
I have the wiring diagram as pdf. That can get you going on the wires and relay right away if you are interested.
Cheers ...... Ole

[mgcjag]

Wireing diagram pdf is in the knowledge base section.....

[215m3]

Hi Toby,
I have the wiring diagram as pdf. That can get you going on the wires and relay right away if you are interested.
Cheers ...... Ole

Hi Ole

Yes please. Could you send them to my email - toby.brittain@bmminiparts.com

Thanks

[Ole-xke1974]

Done !

[dpugh]

Check the fans haven't been rewired to the spare switch on the right hand side. (HRW switch in coupes).

That's what happened to mine, only the seller negated to tell me. I had been driving around for months without the fans going on. I only found out when I left it running outside my house after a drive and it overheated.

For some reason someone had rewired so the switch was the only control. Anyway replaced otter switch, wiring loom for the fans and it all works perfectly. As the wires for the switch were already there, I wired in the switch to bridge the otter switch connections just in case as a manual override. (not how they had it!)

[215m3]

Can someone upload a picture of where the fan wiring meets the loom. It is only £20 ish for a new loom and as mine has been butchered it is a no-brainer

Does this loom have 3 connections to the engine loom?

[Ole-xke1974]

There's a support arm on either side of the radiator going to the "picture frame" (square frame in front of the engine). The RH arm should have the wires strapped to it and the connection to the loom is where the radiator support meets the picture frame.

[215m3]

Thanks Ole, how many wires connect into the main loom?

I have attached a picture with a red circle and I think it is 3 wires. This is Colin's engine from earlier in the post.

[Ole-xke1974]

Toby,
Yes, that shows the connectors.
I'll have to go and look at my car, but it isn't that many.
From memory:
A heavy gauge 12V (brown, I believe) 12V switched on by ignition, a ground (negative) a control wire from the AC relay (not sure if the AC wire is present on a non-ac car. 3 maybe 4 in total.
There are two wires going to the bottom of the radiator for the otter switch.
Cheers ...... Ole