[HOW-TO] Fan override switch fitment

[Noddy]

Righty then.... Following Jam2008's fan switch sales, there has been a bit of confusion over the fitting of them. The switch can be wired in two different ways. The first way is to override the automatic fan cut in whilst the engine is running and the second is to run the fan without the engine running (please note that using this option means that you cannot override the automatic cut in and please for hells sake do not use it to run the fan with the engine running! - In doing so, if the fan automatically kicks in, then the extra power that you are giving it may damage the fan...)

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To wire the switch in for running the fan without the engine running:

- To keep things safe to start, disconnect the battery before you start

- First off you need to find the rubber grommit up behind the glovebox to poke both of the blue wires through (unterminated end). Use a screwdriver to push the wires through the grommit and locate them on the other side of the bulkhead behind the master brake cylinder.

- From here on one of the wires needs to run to the fan at the front of the bay and the other is to goto the battery +ve terminal (alternatively you can route it to the smaller fuse box at the rear of the bay.

- For the live feed, crimp a ring terminal onto the end of the wire and bolt it to either the bolt in the small fuse box or straight onto the +ve of the battery if you have a clamp wich allows for this:)

- For the feed from the switch to the fan run the cable round the bay (via the right hand fuse box and then down and through the slam panel to the fan at the front. - you need to run the cable as far as the black plug on the front of the fan.

- Using one of the splice connectors, attach the cable to the RED lead to the fan

- In the car, mount the switch where you desire and attach the two wires to the switch using the spade terminals that are on the cables when you get the kit.

- Reconnect the battery:)

- This will now allow you to power up the fan WITHOUT the engine running. AS I STATED ABOVE - DO NOT RUN THE FAN WITH THE ENGINE RUNNING IF YOU WIRE IT IN IN THIS WAY - IF THE FAN SHOULD AUTOMATICALLY KICK IN, THE EXTRA POWER THE YOU WOULD BE GIVING IT WOULD DAMAGE THE FAN MOTOR!

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To wire the switch in for running the fan with the engine running:

- As above, disconnect the battery before doing this:)

- First off you need to find the rubber grommit up behind the glovebox to poke both of the blue wires through (unterminated end). Use a screwdriver to push the wires through the grommit and locate them on the other side of the bulkhead behind the master brake cylinder.

- Following this both wires need to run to the cooling system thermostat which is located next to the rocker cover on the right. Depending on what engine you have, this varies from a blue to grey to white terminal (in my case its blue) (out of this will be two wires - one green and one pink)

-To check that you have correctly identified the right terminal, unplug it and start your engine - the engine temperature warning light should come on and the fan will start. (This is the emergency cut in and the fan will continue to run until the ECU has a reading again from the thermostat) - Plug the terminal back in and the light should go off and the fan will stop)

- The two wires that come out of the terminal are what we need to splice into. There are two ways of doing this depending on how tidy you want it done.

- If you want to use the splice connectors provided, then use each one to attach one of the blue leads to the green and pink wires.

- The alternate is what i have done and that is to run the wires straight into the plug and put new connectors onto the ends and into the plug (I will find the part number for the terminals) you will need to dis-assemble the plug and remove the terminals that are there already. Cut these off and run the new cables through the rubber bung (following the existing wires) - strip off some casing from the cables and then crimp new terminals onto the ends of the pairs (one pair blue/green and the other blue/pink)

- Reassemble the plug and reconnect to the sensor

- As before you then need to connect to the switch on the other end to activate the fan.

- PLEASE NOTE THAT WHEN YOU TURN THE FAN ON, THE ENGINE TEMPERATURE WARNING LIGHT WILL COME ON AS THE ECU IS GETTING A FALSE READING - THUS THE FAN COMING ON. (THERE IS A SECOND OR TWO DELAY BETWEEN TURNING THE FAN ON AND IT COMING ON)

WHEN YOU TURN THE FAN BACK OFF, THE LIGHT WILL THEN GO OFF AND THE FAN WILL STOP.

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I'll whack up the pictures to go with this in a bit once i've reduced their size and uploaded them :)

Enjoy - any questions or queries in my description (as i've quickly rushed to finish it), feel free to ask me in here or via PM :) - ENJOY!

[furiomike]

really good guide, and i've got it working. i'm just having massive difficulty getting wires from the car into the engine bay. i push them through but they dont appear anywhere :( lol

[frankie]

if your using the hole he mentioned it should appear below the brake servo on the left hand side.

[jam2008]

excellent guide noddy... repped

[carlos45]

very good guide, for the people who cant get wires through the bulkhead, use a wire coat hanger (or something similar) and tape the wires on the end, then pull through.

[Noddy]

cheers guys, i did finish it in a rush, but i'll get some more photos form my bay tomorrow (brothers got better camera atm) and then i'll whack up some pics :)

[jamie_k]

how would the fan receive extra power if the fan auto kicks in while its already "switched" on? it will still receive 12v no matter what

[Noddy]

i mean that if you power up the fan from the first option and it kicks in it getting two power feeds....

[Andy72]

can you not just take the wires to the thermostatic switch in the side of the rad? as that triggers the feed to the fan power.

[RyVTR]

^^ thats what i was thinking??

[furiomike]

i dont think my car has the thermo thing on the side of the radiator.

and ha! i used the old coat hanger and ducktape trick this afternoon and it finally worked.

[furiomike]

i mounted the switch like this...

http://i23.photobucket.com/albums/b383/kyros_uk/DSC00415.jpg

handbrake kinda covers it over bit its still switchable.

[jamie_k]

i mean that if you power up the fan from the first option and it kicks in it getting two power feeds....

wrong, it both uses the same single power feed, the battery, so it will not overpower at all

[Steve]

do you not need a fuse? take it you are bypassing the fuse in the fuse box?

Also i take it the switches you have has 3 feeds on it?

[Noddy]

nope, their 2 pin switches - I have not fused the switch that runs the fan with the engine off atm as i'm trying to find out exactly what rating of fuse it needs :( - hasn't caused a problem so far....

[Saxo-Slag]

Is this the same wires for all models mate

[Noddy]

indeed it is dude, the only thing that varies is the colour of the temp sensor plug on engine block. on the mk2 1.1s for example its blue.... (front right hand corner on the top of the engine block.)

[gavbey]

30 amp fuse budy. same as in fuse box???

[Andy-Lee]

Why doesn't my temp light come in or my fan kick it when its not connected???:y:
Temp gauge just gets no reading and that's all that happens
help appreciated
Andy

[dannyboy2005]

The 2nd Method, fan running when the engine is on, would it work when the engine is OFF? EG, while on ignition? (All the cockpit gauges work)

[Noddy]

I'll try it in the morning to see if it does, theres only one way to finds out after all :)

[Noddy]

danny - following a couple of tests, i can say the following.

from a fresh start, (ie just after you put the key into the barrel) and turn the ignition to stage 2 (dials engaged), turning the switch to ON has no effect at all. If you was to turn the ignition OFF at this point and remove the key, the fan then comes on in the emergency cooldown. The only way to turn the fan off at this point is to start the engine and turn the switch off to give the ECU a true reading.

If you was to turn the engine off with the fan switched on, it will continue to run until you start the engine again to give the ECU a true reading.

[dannyboy2005]

So it would be better if the engine was running and the fan was on?

Thanks mate!!!!!

[Noddy]

in a nutshell yes it would be. Whilst the engine is running, the cars voltage is at approx 14.4v whereas its about 11.7v (on mine anyway) that extra 3v make a difference as the fan will spin faster with the higher voltage thus moving more air across the rad.

[dannyboy2005]

Ok

I fitted it yesturday (Luckly i never drilled any holes into the dash)

I did it the way that the engine must be running for the fan to work.
I have VTR dials (For a rev counter + TEMP GAUGE) so i spliced into the pink wire iirc and took a wire from the pink wire, to the dials.

Anyway, connect it all up, turned ignition on and the temp gauge shot to the top.
Thought ok, so started engine and it dropped to the bottom. Engine started to get warm (Could tell by the gauge) so i hit the switch, left it for a few seconds and nothing happened. Flicked it the other way and the temperature gauge suddenly dropped, as if i cut the readings from the dials.

How can i over come this problem?

[swampy]

Hmm i have all the items here to make a much improved version!
With an illuminated switch and fused feeds.
Though would cost a few quid more

[saxo_90]

so is there a way that you can get both fans to run automaticaly like when the single fan comes on?

[Noddy]

danny, the pink wire that you've used, is this the one from the top of your thermostat? I'm thinking that yours is not connected right as the needle should not be hitting the top and bottom like that. check that you've got no shorts and that the connections are nice and clean..

saxo_90 - can you expand further to what you mean by both fans running automatically?

[saxo_90]

danny, the pink wire that you've used, is this the one from the top of your thermostat? I'm thinking that yours is not connected right as the needle should not be hitting the top and bottom like that. check that you've got no shorts and that the connections are nice and clean..

saxo_90 - can you expand further to what you mean by both fans running automatically?

if like on my furio where there is one cooling fan ..... i think, is there anyway to install another fan that will come on when the factory fitted on does?

as i was looking to get it fitted and paint it soely for the look of it

[Noddy]

yes you can add another fan to run alongside the other one. obviously you'll need the fan and cowling to go-with. then you'll just need the electrical connector to connect it with - best way is to splice into the wiring at the other fans connection point - you should only need two 10-12" runs of suitable wire to connect them that way.