Manual override; fans

[cully]

my turn!

[bigcheez2k3]

Back to topic, ffs, i'll change it now.

I've got a 3 pin plug, i've just noticed. now i tested the live to the fans etc, it all seems "ok", but the fans do not kick in. one of them is dead, i've just tried manually switching them on, and one works, no the one that works i'm trying to wire up.

As said, i can't just lobb a live and earth on the fan with a switch, as it starts burning the wire up <---- how do i overcome this?

That's already been explained, you use a relay to take the higher power.

This thread has answered my question anyway, as my fans currently don't work either and been considering wiring them up to something.

12v -- relay --- fan ?

I think that's the jist of it, with the switch wired into the relay to power it on.

With an earth too.

[Sambarker]

I've been playing with a new rad temp sensor today as I want to do my own wiring for the cooling fans

It's a 3 pin rad temp switch which was about 3 quid off eBay

Using a thermometer, multimeter and a kettle I have worked out what each pin does.

Basically one of the pins is where you connect your input (be it 12v feed/earth) and then one if the pins becomes live at 82 degrees and the other at 85.

Plan is to wire fans up so that at 82 degrees one fan comes on and the other at 85. I'm also going to wire in a manual override 2 position switch so I can have one or both fans on at any time.

[ginge191]

sounds far too technical i think. Plus, one of the fans is bust.
I've located the relay for the fans, i'll nick that relay and wire it up in a seperate loom i think.

Just reading up on relays, have never had to touch one before. It's like stimulating a lesbian, you "think" you know what to do, but you're not all too sure...

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does this seem reliable info?

-30 = constant [positive (+)] power (usually wired directly to car battery)
-85 = coil ground (wired to the negative (-) battery terminal or any grounded metal panel in the car)
-86 = coil power (wired to the control source. could be a switch, or it could be the car's IGN or ACC circuit.)
-87 = switched [positive (+)] power output. (when the relay coil is powered, lead/pin 87 is connected to lead/pin 30)
-87a = [on 5 lead/pin relays only] this lead/pin is connected to lead/pin 30 when the coil is NOT powered.

[Niall]

Sigh. Why didnt you say this on Sunday? We could of easily got the fans working and fitted a switch!

[ginge191]

Completely forogt

[MissTap_GTI6]

You were too busy actually getting the car going -_-

[Niall]

yeah bastard thing. Next time, buy a brand new bloody starter motor!!

If your up this way any time soon, let me know and ill sort it out

[ginge191]

Thanks babe.. I might be going to Max's tomorrow to help get the other 205 running. Might do the fans at the same time.. I'll keep it updated

[bigcheez2k3]

Let me know how it goes, I'll be interested in your setup.

Think I'll start a new thread on this tomorrow as I want to do this but with a couple extra bits in there.

EDIT: Is there a way I can test the fans to make sure they work? Got a spare set in the shed so if the ones on the car are dud I can swap them over.

[strictly_perv]

I've completely ditched the stock relay and fan set up and have fitted and wired a slim line fan to a manual switch pretty much like cullys diagram.

If you come over tomorrow I'll try and sort it out for you

[ginge191]

Gimmie a moment...

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[cully]

o dear god Nialls at the crayons again!

go look at the drawing i posted..............

[ginge191]

86 goes to a thermostat - ie; my switch?

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o dear god Nialls at the crayons again!

Also, it say's 85 goes to 12v? should it not stay as an earth?

[ginge191]

hmm i followed the diagram to the TEEEE, except i connected the wires where the switch "will be" and manually put the 12V on to make sure it was kicking in, and nope..

so i bridged 2 & 5 (85 & 86) and the fan kicks in, but the relay doesn't want to activate the magnet.

tried another relay, nope.

I am using thin speak cable for the switch, could this be the fault?

Can't see where i've gone wrong..

[Mitch]

Being trying to get my head around this too lately, i get myself so confused its unreal, i came up with this tonight (i believe its correct, if not somebody please tell me) sorry for the tragic attempt of using paint but you get the idea!

   

[Matt]

Anyone got any pictures of how it's done?
Where to wire to, what relay to use etc. going to tackle this in mine at the weekend

[ginge191]

in honesty, i had to clue how to wire up a relay (as in, what a relay ACTUALLY does)

go into google and read around. once you understand that, wiring it is fairly simple.

tools you/i needed

1 X relay
Wire cutters
A fair amount of wire
Crimps/connectors including spades for the relay
1 X switch

[Matt]

So what type of relay do you need? Will go google, but is there different types of relay? If so what's best to use?

[ginge191]

I don't think so; "buy" a relay from the scrapers. Match up the numbers on the relay to the wires required in cullys picture above.
Temp sensor in his picture is just a normal switch

[Matt]

Sorted. Scrappers at the weekend then, relay and wiring

Did you find it easy to wire up?

[aggyj17]

Being trying to get my head around this too lately, i get myself so confused its unreal, i came up with this tonight (i believe its correct, if not somebody please tell me) sorry for the tragic attempt of using paint but you get the idea!

If I use this diagram can I use the fan sensor in the thermostat housing and wire it up instead of the switch?? I will also have a switch but its for the mrs car and want it to come on automatically aswell so if she forgets it wont boil the car

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[Mitch]

I wouldnt know sorry dude, it fried my head working out that diagram the other week, matt, i used one of the green relays out of the standard fan unit, used it a fair amount on the way to pug fest, and the last few days in this weather we are having, all seems to be ok!

[Mattcheese31]

in honesty, i had to clue how to wire up a relay (as in, what a relay ACTUALLY does)

go into google and read around. once you understand that, wiring it is fairly simple.

tools you/i needed

1 X relay
Wire cutters
A fair amount of wire
Crimps/connectors including spades for the relay
1 X switch

i'm pretty sure it was me that explained it to you . . .

[ginge191]

Sorted. Scrappers at the weekend then, relay and wiring

Did you find it easy to wire up?

erm it's dependent on your competence i guess; for cully and the like, he can do it in his sleep, for myself whom his electrically numb, it took a fair bit of figuring out and literally copied the layout from paper; i printed it out and followed it to the T.

i'm pretty sure it was me that explained it to you . . .

you said you WOULD dumb it down to be understood by a 7 year old, but never did :'(