Styling putting the fan on a switch-how?

[99sei]

think ive seen a thread on this but cant find it.

now its all mot'd i want to sort out heating issues first, so i want to add a switch to the fan to turn on when ever i want. i aint got a clue how to do this though

can any one help?

 

[Luke M]

i think you will need to cut in to the switch wire from the thermostat. im guessing its powered by a relay, so you want the switch to switch the relay.

 

[rallycinq]

You need to cut into the wires for the thermo switch on the rad. Don't disconnect the original wires as you might forget to put the switch on and the thermo switch will remember.

Use a 10amp switch.

Cheers

D

 

[99sei]

You need to cut into the wires for the thermo switch on the rad. Don't disconnect the original wires as you might forget to put the switch on and the thermo switch will remember.

Use a 10amp switch.

Cheers

D

thats a good idea, so just cut the wire, run it to the switch then a positive, yeah?

 

[arc]

i've done this on my car, used an automotive relay. I cut the negative wire (black) from the fan switch, wired one end into the relay the other into the other end of the relay. Took a wire from earth to one of the other pins on the relay. Then ran low ampage tiny little cables to the dash, and used a tiny little switch. Wired one end of that into a fused 12v line, the other end went to the relay. The final relay connection went to ground.

So.. when you flick the switch, it powers up the relay and moves the fan from thermo control to permantly on. Turn the switch off and it goes back to thermo control. I used a relay as i didnt want high ampage cable running through my dash, or to have a bulky switch.


here is the fan relay:

and here is the fan switch:

and attached is a lovely paint diagram of what was done.

 

[99sei]

love the drawing

have you asked santa for a box of crayons for xmas

think i get it, will have a look at it 2moz and let you know how i get on

 

[rallycinq]

thats a good idea, so just cut the wire, run it to the switch then a positive, yeah?

Nope, there is no need for an additional power supply. tap into both wires, run a piece of 10 amp twin core to a 10 amp switch, or, use the relay method and you can then use switching cable to the dash with a 1 amp rated switch.

Cheers

D

 

[arc]

or a single piece of 10amp, and then ground the other end of the switch in the dash somewhere.

 

[Bushboy]

easy way would be to just bridge the wires.

youve got the +12 going into the fan switch, splice into that and run a wire into the dash, connect it to a switch, then run a wire from the other side of the switch and splice it into the -12 from the fan. when you flick the switch on the dash, it will act as if the fan switch has been turned on and will turn on the fan. the fan switch circuit will still work when you have the switch on the dash turned off.

 

[arc]

the fan switches negative, there is no +12v going into it. but other than that you've just said exactly what everyone else has said there chris

 

[Bushboy]

ah well i dont care whats positive or negative works anyway

 

[woodins]

Sorry i am a complete Noob. What would be the downsides of using this system? Say a scatty numb-nuts like meself was to leave this on, would the fan eventually drain the battery of power if left on whilst driving for a long time?


Sorry going OTT after my HG going on my Cinq (see technical post) lol.

 

[arc]

i might be wrong on this.. but with the fan on, and the car at speed - the fan won't be able to keep up with the airflow, so it'll be forced to spin quicker than it's meant to.. wearing it out quicker.

for your car, i'd look at getting a punto GT fan switch first - they switch at 82c i think

 

[woodins]

. . . . . . . almost types in "FORD" on autotrader website . . . . . . almost

 

[rallycinq]

Sorry i am a complete Noob. What would be the downsides of using this system? Say a scatty numb-nuts like meself was to leave this on, would the fan eventually drain the battery of power if left on whilst driving for a long time?


Sorry going OTT after my HG going on my Cinq (see technical post) lol.

While driving one has to assume that the engine is turning. Again, an assumption that your alternator is working, would mean that the battery can't run down.

Leaving the fan running with the engine switched off, different matter, about an hour, I reckon.

Cheers

D

 

[99sei]

you'd notice if the cars fan was on when leaving it, its so dam loud its impossible too

 

[woodins]

LOL true Sei.

Was round me dads last night. He feels a bit guilty that he has moved away and that i have had to take care of my car woes on my own so he has offered to fit a fan switch for me.

 

[99sei]

ohhh get him to do one for me too

 

[99sei]

right the bumper is off ready to be started on tomorrow, can i use one of the relays where all the fuses are (got a few spare)

 

[rallycinq]

Not really. The idea is to put the relay as close to the item to be switched, in this case the fan, to reduce the amount of power loss in the cables. I would mount the relay on the crossmember and take the switching wire back to the dash.

Cheers

D